CN114906110A

CN114906110A - Control system

Info

Publication number: CN114906110A
Application number: CN202210104571.4A
Authority: CN
Inventors: 田中基大; 塚田裕介; 北村毅史
Original assignee: Nabtesco Corp; Nabtesco Automotive Corp
Current assignee: Nabtesco Corp; Nabtesco Automotive Corp
Priority date: 2021-02-08
Filing date: 2022-01-28
Publication date: 2022-08-16
Anticipated expiration: 2042-01-28
Also published as: CN114906110B; JP2022121067A

Abstract

The invention provides a control system, which can grasp the abnormality without additionally arranging a communication line for transmitting the abnormality. A command device of a control system is provided with: a main ECU that calculates an operation command pressure and transmits a command signal indicating the operation command pressure to a valve control device; and a superimposing circuit that transmits the command signal and the specific signal to the valve control device when the main ECU is normal, and transmits the command signal to the valve control device without transmitting the specific signal to the valve control device when the main ECU is abnormal. A valve control device of a control system is provided with: a superimposed signal detection circuit that detects a specific signal from a signal received from the command device; and a sub-ECU that controls the intake valve and the exhaust valve in accordance with the received command signal when the specific signal is detected, and does not control the intake valve and the exhaust valve in accordance with the command signal when the specific signal is not detected.

Description

Control system

Technical Field

The present invention relates to a control system.

Background

Patent literature 1 describes a control system in which a plurality of devices are connected via a communication path. In the control system, each device diagnoses the state of other devices than itself and exchanges the results thereof via a communication path, thereby grasping the state of the entire system. In addition, the device has a self-diagnosis function of diagnosing its own state.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2012-25390

Disclosure of Invention

Problems to be solved by the invention

In the control system described in patent document 1, since the state of the entire system is grasped by exchanging the diagnostic results via the communication path, it is necessary to improve the reliability of the hardware responsible for the communication, and a dedicated line is necessary to reliably transmit the abnormality of the device. In this case, hardware for performing communication through the dedicated line needs to be additionally provided, and thus the cost increases. Therefore, it is required to grasp the abnormality without additionally providing a communication line for transmitting the abnormality.

Means for solving the problems

A control system for solving the above problem is a control system for controlling a valve that adjusts compressed air supplied to a brake device for generating a braking force of a vehicle, the control system including: a command device that calculates an operation command pressure of the valve; and a valve control device connected to the command device via a communication line and configured to control an operation of the valve in accordance with the calculated operation command pressure, wherein the command device includes: a command transmission unit that calculates the operation command pressure and transmits a command signal indicating the operation command pressure to the valve control device; and a signal transmission circuit that transmits the command signal and a specific signal different from the command signal to the valve control device via the communication line when the command transmission unit is normal, and transmits the command signal to the valve control device via the communication line without transmitting the specific signal to the valve control device when the command transmission unit is abnormal, the valve control device including: a detection circuit that detects the specific signal from a signal received from the instruction device via the communication line; and a valve control unit that controls the valve in accordance with the received command signal when the specific signal is detected, and that does not control the valve in accordance with the command signal when the specific signal is not detected.

According to the above configuration, the command device includes a signal transmission circuit that transmits the command signal and transmits the specific signal when the command transmission unit is normal, and transmits the command signal but does not transmit the specific signal when the command transmission unit is abnormal, and the valve control device includes a detection circuit that detects the specific signal. When the specific signal is detected, the valve is controlled in accordance with the command signal, and when the specific signal is not detected, the valve is not controlled in accordance with the command signal. Therefore, the valve control device can grasp the abnormality of the command transmitting portion without separately providing a communication line for transmitting the abnormality.

In the control system, it is preferable that the signal transmission circuit superimposes the specific signal having a frequency band different from a frequency band of the command signal on the communication line when the command transmission unit is normal, and the signal transmission circuit does not superimpose the specific signal and the detection circuit detects the specific signal superimposed on the communication line when the command transmission unit is abnormal.

In the control system, it is preferable that the valve control device includes a filter for removing a signal other than a frequency band of the command signal, between the detection circuit and the valve control unit.

In the control system, it is preferable that the signal transmission circuit is a first signal transmission circuit, the detection circuit is a second detection circuit, the valve control device includes a second signal transmission circuit, the second signal transmission circuit transmits a state signal indicating a state of the valve and a specific signal different from the state signal to the command device via the communication line when the valve control unit is normal, the second signal transmission circuit transmits the status signal to the command device via the communication line when the valve control unit is abnormal, without sending the specific signal to the command device, the command device being provided with a first detection circuit, the first detection circuit detects a specific signal different from the state signal from a signal received from the valve control device via the communication line.

A control system for solving the above problem is a control system for controlling a valve that adjusts compressed air supplied to a brake device for generating a braking force of a vehicle, the control system including: a command device that calculates an operation command pressure of the valve; and a valve control device connected to the command device via a communication line and configured to control an operation of the valve in accordance with the calculated operation command pressure, wherein the command device includes: a command transmission unit that calculates the operation command pressure and transmits a command signal indicating the operation command pressure to the valve control device; and a signal transmission circuit that transmits the command signal to the valve control device via the communication line without transmitting a specific signal different from the command signal to the valve control device when the command transmission unit is normal, and that transmits the specific signal to the valve control device via the communication line without transmitting the command signal to the valve control device when the command transmission unit is abnormal, the valve control device including: a detection circuit that detects the specific signal from a signal received from the instruction device via the communication line; and a valve control unit that controls the valve in accordance with the received command signal when the specific signal is not detected.

According to the above configuration, the command device includes a signal transmission circuit that transmits the command signal without transmitting the specific signal when the command transmission unit is normal, and transmits the specific signal without transmitting the command signal when the command transmission unit is abnormal, and the valve control device includes a detection circuit that detects the specific signal. When the specific signal is not detected, the valve is controlled in accordance with the command signal. Therefore, the valve control device can grasp the abnormality of the command transmitting portion without separately providing a communication line for transmitting the abnormality.

In the control system, it is preferable that the signal transmission circuit fixes the voltage of the communication line to a predetermined voltage different from the voltage of the communication line when the command transmission unit is normal, and the detection circuit detects the specific signal by detecting that the voltage of the communication line is fixed to the predetermined voltage when the command transmission unit is abnormal.

In the control system, it is preferable that the signal transmission circuit is any one of a circuit capable of short-circuiting the communication line to a power source when the command transmission unit is abnormal, a circuit capable of short-circuiting the communication line to ground when the command transmission unit is abnormal, and a circuit capable of disconnecting the communication line when the command transmission unit is abnormal.

In the control system, it is preferable that the signal transmission circuit is a first signal transmission circuit, the detection circuit is a second detection circuit, the valve control device includes a second signal transmission circuit, the second signal transmission circuit transmits a state signal indicating a state of the valve to the command device via the communication line without transmitting a specific signal different from the state signal to the command device when the valve control unit is normal, the second signal transmission circuit transmits a specific signal different from the state signal to the valve control device via the communication line without transmitting the command signal to the valve control device when the valve control unit is abnormal, and the command device includes a first detection circuit that detects that the state signal is not transmitted to the valve control device from a signal received from the valve control device via the communication line The same specific signal.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, it is possible to grasp an abnormality without additionally providing a communication line for transmitting the abnormality.

Drawings

Fig. 1 is a schematic diagram showing the overall structure of an air pressure brake system.

Fig. 2 is a schematic diagram of a first embodiment of a brake control system including an air pressure circuit.

Fig. 3 is a schematic diagram showing the configuration of the brake control system according to this 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 gas tank communicates with the brake mechanism as the air pressure circuit of the embodiment.

Fig. 6 is a flowchart showing a processing for dealing with an abnormality in the brake control system according to the embodiment.

Fig. 7 is a flowchart showing a releasing process of the brake control system according to the embodiment.

Fig. 8 is a flowchart showing normal communication of the brake control system according to the embodiment.

Fig. 9 is a flowchart showing communication at the time of an abnormality of the brake control system of the embodiment.

Fig. 10 is a schematic diagram showing the configuration of a brake control system according to the second embodiment.

Fig. 11 is a schematic diagram showing the configuration of the communication disconnection circuit according to this embodiment.

Fig. 12 is a schematic diagram showing the configuration of the communication disconnection circuit according to this embodiment.

Fig. 13 is a schematic diagram showing the configuration of the communication disconnection circuit according to this embodiment.

Fig. 14 is a flowchart showing normal-time communication of the brake control system of the embodiment.

Fig. 15 is a flowchart showing communication at the time of an abnormality in the brake control system of the embodiment.

Detailed Description

(first embodiment)

Hereinafter, a first embodiment in which the control system is embodied as a brake control system will be described with reference to fig. 1 to 9. The brake control system controls a valve that adjusts delivery of compressed air to a brake device for generating a braking force for the vehicle. The brake control system is a system for coping with driver's abnormality, and is mounted to an air pressure brake system mounted on a vehicle such as a bus in a manner to be mounted later. The brake control device is post-installed by adding a control program related to a system for responding to a driver's abnormality to an existing control device.

As shown in fig. 1, an air pressure brake system 11 mounted on a vehicle 10 is a command system for controlling a brake mechanism by air pressure and is a system including a full air brake (full air brake) of an air pressure-driven brake mechanism. The air pressure brake system 11 includes an air tank 12 for storing compressed air generated by a compressor (not shown). The gas 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 that stores compressed air for applying braking force to the front wheels of the vehicle 10. The second tank 12B is a tank that stores compressed air for applying braking force to the rear wheels. The third tank 12C is a tank for storing compressed air used for other purposes. The first tank 12A is connected to a front pressure chamber 13A of the brake valve 13, and the second tank 12B is connected to a rear pressure chamber 13B 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 a protection valve 14A.

The brake valve 13 is connected to the relay valve 15 via an air pipe 18. When the brake pedal 13C of the brake valve 13 is operated by the driver, an air pressure signal is output from the brake valve 13 to the relay valve 15. The relay valve 15 is connected to the gas tank 12 through an air pipe, not shown. When the relay valve 15 receives an air pressure signal from the brake valve 13, a large amount of compressed air stored in the air tank 12 is supplied to the relay valve 15 via the air pipe. A large amount of compressed air supplied to the relay valve 15 is supplied to a Brake chamber 17 via an ABS (Anti-lock Brake System) control valve 16. The brake chamber 17 generates braking force on the wheels due to the supplied air. The ABS control valve 16 and the brake chamber 17 constitute an air pressure-driven brake mechanism. The operation on the brake pedal 13C corresponds to a braking operation by the driver.

An Emergency Driving Stop System (EDSS) is mounted on the air pressure brake System 11 of the existing vehicle 10, and the Emergency Driving Stop System causes the vehicle 10 to Stop urgently by an operation of a driver or a passenger other than the driver when an abnormality occurs in the driver. In the system for coping with the driver's abnormality, a Pressure Control Module (PCM) 20 is provided midway in an air pipe 18 of a command system for connecting the brake valve 13 and the relay valve 15. The pressure control module 20 has: a first port P1 connected to the gas tank 12 (third 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. Since the pressure control module 20 is provided between the brake valve 13 and the relay valve 15, it can be mounted to the air pressure brake system 11 having a brake mechanism other than the air pressure drive type.

Referring to fig. 2, 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 constitutes a driver abnormality coping system 50 together with the main ECU 31. The main ECU31 corresponds to a command device. The sub ECU32 corresponds to a valve control device.

The main ECU31 and the sub-ECU 32 each include a calculation unit, a communication interface unit, a volatile storage unit, and a nonvolatile storage unit. The calculation unit is a computer processor and controls the air pressure brake system 11 in accordance with a control program stored in a nonvolatile storage unit (storage medium). The arithmetic unit may realize at least a part of the processing executed by itself by a circuit (circuit) such as an ASIC. The control program may be executed by one computer processor or may be executed by a plurality of computer processors. The main ECU31 and the sub-ECU 32 are connected to a CAN (Controller Area Network) 33 as an in-vehicle Network, and transmit and receive various information to and from each other.

When the operation switch 51 is turned on, the main ECU31 receives a stop signal for stopping the vehicle 10 in an emergency, which is transmitted from the operation switch 51. When the release switch 52 is turned on, the main ECU31 receives a release signal transmitted from the release switch 52. The operation switch 51 and the release switch 52 are switches assumed to be operated by the driver, and are provided near the driver seat. When the operation switch 51 is turned on, the driver should operate the system 50 in an abnormal state. The release switch 52 is a switch for stopping the operation of the system 50 when the driver is in an abnormal state and the system should malfunction. When the operation switch 51 is turned on, the master ECU31 controls the air pressure brake system 11 to perform the main braking. The service braking is braking for decelerating the vehicle 10 at a deceleration larger in absolute value than the slow braking and finally stopping the vehicle. The slow brake is a brake in which the absolute value of deceleration is small, or a brake in which the time for which the brake is applied is short, and is a brake capable of returning to normal running when the release switch 52 is operated immediately after that.

When the passenger seat operation switch 53 is turned on, the main ECU31 receives a stop signal transmitted therefrom to bring the vehicle 10 to an emergency stop. The passenger seat operation switch 53 is a switch that assumes an operation by a passenger other than the driver. The passenger seat operation switch 53 is provided at a position other than the driver seat, that is, a position that can be operated by a passenger other than the driver. When the passenger seat operation switch 53 is turned on, the main ECU31 controls the air pressure brake system 11 to perform slow braking.

The master ECU31 includes an acquisition unit 31A that acquires a correlation between an actual brake pressure at the time of brake operation control of the air pressure brake system 11 by the driver and a deceleration of the vehicle 10 at the time of braking of the vehicle 10 at the actual brake pressure. The main ECU31 is provided with an estimating portion 31B that estimates a target brake pressure for decelerating the vehicle 10 at a desired deceleration based on a correlation between the actual brake pressure and the deceleration. The main ECU31 includes a control unit 31C, and when receiving the stop signal, the control unit 31C controls the air pressure brake system 11 based on the target brake pressure estimated by the estimation unit 31B to stop the vehicle 10. The acquisition portion 31A acquires speed information from the speed sensor 55 via the CAN 33, and acquires actual brake pressure from the second pressure sensor 39 via the CAN 33 and the sub-ECU 32. The acquisition section 31A stores the deceleration obtained from the speed and the actual brake pressure at that time in the storage section 31D, and acquires the correlation between the actual brake pressure and the deceleration. The estimating unit 31B stores the estimated target brake pressure in the storage unit 31D. The initially set target brake pressure used until the estimation is completed is stored in the storage unit 31D.

When the system 50 is to be activated when the driver is in an abnormal state, the main ECU31 generates an operation command including the target brake pressure of the air pressure brake system 11 estimated by the estimation unit 31B, and instructs the sub-ECU 32 to bring the deceleration obtained from the current running speed of the vehicle 10 close to the target deceleration, which is the target value. The target deceleration can be changed by updating the data stored in the storage unit 31D of the main ECU 31. For example, in the case where the vehicle 10 is a bus, the absolute value of the target deceleration is made small, assuming that a standing passenger is present in the vehicle. In addition, when the vehicle 10 is a high-speed bus in which all passengers are seated, the absolute value of the target deceleration may be made larger than that of a public bus. The target deceleration may be changed according to the weight and length of the vehicle 10.

When the system 50 is to be operated in the event of an abnormality in the driver, the main ECU31 outputs instruction signals to the in-vehicle device 56 and the out-of-vehicle device 57. The in-vehicle device 56 is, for example, an accelerator interlock mechanism that disables the operation of an accelerator pedal. When an abnormality occurs, the main ECU31 operates the accelerator interlock mechanism. In addition, a notification buzzer provided in the vehicle interior, a notification lamp provided in the vehicle interior, or the like may be provided as the in-vehicle device 56. For example, when an abnormality occurs, the main ECU31 outputs a sound from the notification buzzer, and turns on or blinks the notification lamp. The vehicle exterior device 57 is, for example, an air horn device 14B, a hazard lamp, a brake lamp, or the like. For example, when an abnormality occurs, the main ECU31 drives the protection valve 14A and the like to supply air to the air horn device 14B to generate a warning sound, and turns on or blinks the hazard lamps and the brake lamps.

The sub-ECU 32 is housed in the pressure control module 20, and controls various valves of the pressure control module 20. The pressure control module 20 has a first supply path 23 connected to the gas 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 wheel disposed in front via the relay valve 15, and the rear air supply path 38 is connected to the brake chamber 17 of the wheel disposed in rear.

A relay valve 25 is connected to an intermediate portion of the first supply path 23. The relay valve 25 has an outlet 25A, and the outlet 25A is connected to an exhaust portion 58 having a muffler. The relay valve 25 has a pilot port 25B. The pilot port 25B is connected to a branch line 26 branching from the first supply path 23. When the air pressure applied from the branch passage 26 to the pilot port 25B is a predetermined pressure such as atmospheric pressure, the relay valve 25 is in an exhaust state in which it is blocked from the first supply passage 23 by the biasing force of a biasing spring or the like. When the relay valve 25 is in the exhaust state, the flow of air from the air tank 12 to the front air supply path 37 and the rear air supply path 38 is shut off. When the relay valve 25 is in the exhaust state, the downstream side of the relay valve 25 in the first supply path 23 communicates with the exhaust portion 58, and the compressed air on the downstream side of the relay valve 25 in the first supply path 23 is exhausted to reach a predetermined pressure such as atmospheric pressure.

On the other hand, when the air pressure applied from the branch passage 26 to the pilot port 25B reaches a driving pressure higher than a predetermined pressure such as atmospheric pressure, the relay valve 25 is in a supply state communicating with the first supply path 23 against the biasing force of a biasing spring or the like. 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 communicates with the front air supply path 37 and the rear air supply path 38. When the pressure on the outlet side (secondary side) is too high, the relay valve 25 blocks the communication state of the first supply path 23 and enters an exhaust state.

One end of the branch path 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 passage 26. The intake valve 27 and the exhaust valve 28 are solenoid valves and are driven by the sub ECU 32. The intake valve 27 is provided upstream of the exhaust valve 28 (in the gas tank 12) in the branch passage 26. The intake valve 27 is switched in operation by turning on/off (driving/non-driving) the power supply from the sub-ECU 32 via the wiring 27A. The intake valve 27 is in a closed position for closing the branch passage 26 in a non-driving state in which the power supply is cut off. The intake valve 27 is set to an open position that opens the branch passage 26 in a driving state where the power supply is turned on.

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

Further, a first pressure sensor 35 and a signal supply path 29 for supplying an air pressure signal to the relay valve 25 are connected to the branch path 26 at intermediate positions between the intake valve 27 and the exhaust valve 28. 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.

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 for the front wheels. The double check valve 36A allows the supply of compressed air from the higher pressure side of the third supply path 30 and the front signal supply path 24A, and cuts off the supply of compressed air from the lower side. A second pressure sensor 39 is connected to the front air supply path 37. The second pressure sensor 39 outputs the detected pressure to the sub-ECU 32.

The other 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 braking force to the rear wheels. The double check valve 36B allows the supply of compressed air from the higher pressure side of the third supply path 30 and the rear signal supply path 24B, and cuts off the supply of compressed air from the lower side.

With reference to fig. 3, the communication between the main ECU31 and the sub-ECU 32 of the brake control system will be described. In the brake control system, even if there is an abnormality in the main ECU31, the sub-ECU 32 can grasp the abnormality of the main ECU 31. The main ECU31 includes a self-diagnosis unit 31E for performing self-diagnosis. The self-diagnosis section 31E diagnoses whether or not the master ECU31 and the first CAN transceiver circuit 41A are abnormal.

As shown in fig. 3, the main ECU31 and the sub-ECU 32 are connected via the CAN 33. The CAN 33 corresponds to a communication line. Although not shown in fig. 2, the main ECU31 includes a first communication unit 41 that performs CAN communication. The main ECU31 and the first communication unit 41 function as a command device 1 that calculates an operation command pressure of the relay valve 25. Similarly, although not shown in fig. 2, the sub-ECU 32 includes a second communication unit 42 that performs CAN communication. The sub-ECU 32 and the second communication unit 42 are connected to the command device 1 via a communication line, and function as the valve control device 2 that controls the operations of the intake valve 27 and the exhaust valve 28 in accordance with the calculated operation command pressures. CAN communication is a two-wire differential mode, and communication is performed by regarding a potential difference between two communication lines as a bit (bit). The CAN communication is characterized in that communication CAN be performed even if noise enters a communication line as long as the potential difference does not change, and therefore CAN communication noise resistance is high. The operation command pressure may be the air pressure output from the relay valve 25 or the pressure input to the pilot port 25B. The sub ECU32 drive-controls the intake valve 27 and the exhaust valve 28 so that the air pressure output from the relay valve 25 or the pressure input to the pilot port 25B becomes an operation command pressure.

The first communication unit 41 includes, in order from the main ECU31, a first CAN transceiver circuit 41A, a first Common Mode Noise Filter (CMNF) 41B, and a superimposing circuit 41C. The first CAN transceiver circuit 41A, the first CMNF 41B, and the superimposing circuit 41C are connected in series.

The first CAN transceiver circuit 41A is a circuit that transmits a signal to a communication line in the CAN protocol and receives a signal of the communication line. The first CMNF 41B is a circuit that removes common mode noise included in a communication line to improve signal skew and passes a differential signal. The superimposing circuit 41C is a circuit that superimposes a specific signal having a frequency band different from the frequency band used in a normal state on the communication line when the command transmitting unit is normal, and stops superimposing the specific signal when the command transmitting unit is abnormal. That is, the superimposing circuit 41C superimposes an alternating current signal (superimposed signal) as a specific signal on the communication line. Here, the amplitude and frequency of the alternating current signal can be changed, and the amplitude and frequency of the alternating current signal are determined by the circuit so that the superimposed signal does not become a noise source. The main ECU31 and the first CAN transceiver circuit 41A function as a command transmitting unit that calculates an operation command pressure and transmits a command signal indicating the operation command pressure to the valve control device 2.

The superimposing circuit 41C functions as a signal transmission circuit that transmits the command signal and the specific signal different from the command signal to the valve control device 2 via the communication line when the command transmission unit is normal, and transmits the command signal to the valve control device via the communication line without transmitting the specific signal to the valve control device 2 when the command transmission unit is abnormal. That is, the superimposing circuit 41C superimposes a specific signal having a frequency band different from the frequency band of the command signal on the communication line. When it is diagnosed that there is an abnormality by the self-diagnosis of the self-diagnosing unit 31E or an abnormality is detected by a sensor in the device, the main ECU31 outputs an abnormality signal to the superimposing circuit 41C. When receiving the abnormal signal, the superimposing circuit 41C stops superimposing the superimposed signal on the communication line, and transmits the command signal to the valve control device 2 via the communication line. Therefore, the superimposing circuit 41C superimposes the superimposed signal on the communication line when the command transmitting unit is normal, and does not superimpose the superimposed signal on the communication line when the command transmitting unit is abnormal. As a result, the superimposing circuit 41C generates different signals when the command transmitting unit is normal and when the command transmitting unit is abnormal.

The second communication unit 42 includes a second CAN transceiver circuit 42A, a second Common Mode Noise Filter (CMNF) 42B, and a superimposed signal detection circuit 42C in this order from the sub-ECU 32. The second CAN transceiver circuit 42A, the second CMNF42B, and the superimposed signal detection circuit 42C are connected in series.

The second CAN transceiver circuit 42A is a circuit that transmits a signal to a communication line in the CAN protocol and receives a signal of the communication line. The second CMNF42B is a circuit that improves signal skew by removing common mode noise included in the communication line and passes a differential signal. Therefore, the second CMNF42B removes the superimposed signal other than the frequency band of the command signal superimposed on the communication line. Therefore, the superimposed signal does not affect CAN communication. The superimposed signal detection circuit 42C is a circuit that detects a superimposed signal, which is an alternating current signal superimposed on the communication line.

The superimposed signal detection circuit 42C functions as a detection circuit that detects a specific signal from a signal received from the command device 1 via the communication line, and the superimposed signal detection circuit 42C detects a specific signal superimposed on the communication line in a frequency band different from the frequency band of the command signal. Specifically, the superimposed signal detection circuit 42C includes a voltage detection circuit 42D. The voltage detection circuit 42D can determine the presence or absence of the superimposed signal by detecting the voltage waveform. In the voltage detection circuit 42D, since the capacitor is connected in series to the communication line, a signal in which the dc component is blocked is input to the voltage detection circuit 42D. Further, a large resistance may be provided instead of the capacitor. The voltage detection circuit 42D may detect the peak hold, half-wave rectification, or full-wave rectification, and determine whether or not the superimposed signal is present. When the superimposed signal is not included, the voltage detection circuit 42D determines that the abnormality occurs, and outputs an emergency command to the sub-ECU 32. The sub-ECU 32 causes the intake valve 27 and the exhaust valve 28 of the pressure control module 20 to perform emergency operation via the drive circuit 32A. Here, the emergency operation is an operation performed regardless of the command signal. For example, the emergency operation is an operation of stopping the vehicle 10 by driving the intake valve 27 and the exhaust valve 28 and supplying compressed air from the relay valve 25. The emergency operation may be an operation in which the vehicle 10 is decelerated to a predetermined speed or less without stopping the vehicle 10. When the specific signal is detected, the sub-ECU 32 controls the intake valve 27 and the exhaust valve 28 in accordance with the received command signal. When the specific signal is not detected, the sub-ECU 32 functions as a valve control unit that does not control the intake valve 27 and the exhaust valve 28 in accordance with the command signal.

Next, the operation of the pressure control module 20 will be described with reference to fig. 4 and 5. Fig. 4 shows the air pressure circuit 22 in a case where the operation switch 51 and the passenger seat operation switch 53 are not on-operated.

As shown in fig. 4, the sub-ECU 32 deactivates the intake valve 27 and the exhaust valve 28 when the operation switch 51 and the passenger seat operation switch 53 are not turned on. In this case, the intake valve 27 is in the closed position, and the exhaust valve 28 is in the open position. Accordingly, the portion of the branch passage 26 downstream of the intake valve 27 is at a predetermined pressure such as atmospheric pressure due to the open position of the exhaust valve 28. Therefore, the pressure of the air applied to the pilot port 25B also becomes a predetermined pressure, and therefore the relay valve 25 is in the exhaust state. When the relay valve 25 is in the exhaust state, the compressed air in the third supply path 30 and the downstream side of the relay valve 25 in the first supply path 23 is discharged from the discharge portion 58, and the pressure in the third supply path 30 becomes a predetermined pressure. When the brake pedal 13C is depressed, an air pressure signal is supplied to the front signal supply path 24A and the rear signal supply path 24B. Accordingly, the pressures of the front signal supply path 24A and the rear signal supply path 24B become higher than the pressure of the third supply path 30, and therefore the

double check valves

36A and 36B cut off the flow of air 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, the air pressure signal is supplied to the relay valve 15, whereby a large amount of compressed air is supplied from the air tank 12 to the relay valve 15. When the relay valve 15 supplies compressed air to the brake chamber 17, braking force is applied to the wheels. Further, 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 in a case where at least one of the operation switch 51 and the passenger seat operation switch 53 is turned on. When at least one of the operation switch 51 and the passenger seat operation switch 53 is turned on, the sub-ECU 32 receives the pressure instruction transmitted from the main ECU 31. The sub-ECU 32 drives the intake valve 27 and the exhaust valve 28 based on the pressure indication. Thereby, the intake valve 27 is in the open position, and the exhaust valve 28 is in the closed position. The compressed air in the air tank 12 is supplied to a branch passage 26 between an intake valve 27 and an exhaust valve 28 via a first supply passage 23. When the pressure in the branch passage 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 set to the supply state. Thereby, the compressed air is supplied to the third supply path 30 via the first supply path 23 and the relay valve 25.

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

By providing the pressure control module 20 between the brake valve 13 and the relay valve 15 in this manner, when the operation switch 51 and the passenger seat operation switch 53 are turned on, the command system of the air pressure drive type is switched from the system via the brake valve 13 to the system in which air is directly supplied from the air tank 12. Therefore, even if the air pressure signal from the brake valve 13 is not received, the brake chamber 17 can be operated to generate a braking force.

In addition, the sub-ECU 32 acquires the detection pressures from the first pressure sensor 35 and the second pressure sensor 39 at predetermined timings. For example, when the relay valve 25 is maintained in the supply state, the sub-ECU 32 drives or does not drive the intake valve 27 and the exhaust valve 28 so that the pressure detected by the first pressure sensor 35 falls within a predetermined range. In addition, in the case where the main ECU31 sends the sub-ECU 32a pressure instruction so that the pressure rises in stages 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 value. When the sub-ECU 32 determines that the detected pressure has not reached the first pressure threshold value, 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 reaches the first pressure threshold value, the sub-ECU 32 deactivates the intake valve 27 and the exhaust valve 28 to shut off the relay valve 25. Then, the sub-ECU 32 waits for the next pressure instruction from the main ECU 31.

Next, a process of the processing performed by the main ECU31 in response to an abnormality will be described with reference to fig. 6 and 7. The process shown in fig. 6 is a process for controlling the air system, and is started when the operation switch 51 or the passenger seat operation switch 53 is operated and the main ECU31 receives a stop signal transmitted from these switches. It is assumed that the main ECU31 acquires the vehicle information from the speed sensor 55 at a predetermined timing.

As shown in fig. 6, when the stop signal is received, the main ECU31 determines whether or not the passenger seat operation switch 53 is operated (step S21). That is, the main ECU31 determines whether the received stop signal is a signal from the operation switch 51 or a signal from the passenger seat operation switch 53. When the main ECU31 determines that the operation switch 51 has been operated (step S21: no), the process proceeds to step S24.

On the other hand, when the main ECU31 determines that the passenger seat operation switch 53 is operated (step S21: YES), it instructs the sub ECU32 of the target brake pressure required for the slow braking (step S22). The main ECU31 sends the target brake pressure for achieving the target deceleration for the mild braking, which is stored in its own storage unit 31D, to the sub ECU 32. The sub-ECU 32 drives the intake valve 27 and the exhaust valve 28 (see fig. 4) as described above based on the instruction of the target brake pressure.

The main ECU31 determines whether or not a predetermined time has elapsed from a time point at which the target brake pressure is transmitted to the sub-ECU 32, a time point at which the vehicle 10 starts decelerating, or a time point at which a predetermined response signal from the sub-ECU 32 is received (step S23). The predetermined time is a time required for the driver to operate the release switch 52 in a case where the passenger seat operation switch 53 is erroneously operated although the driver is in a normal state. If the predetermined time has not elapsed (no in step S23), the main ECU31 continues the slow braking while instructing the sub-ECU 32 of the target brake pressure (step S22).

On the other hand, when the main ECU31 determines that the predetermined time has elapsed (step S23: YES), it instructs the sub-ECU 32 of the pressure required for the main braking (step S24). The main ECU31 transmits the target brake pressure for achieving the target deceleration for main braking, which is stored in its own storage portion 31D, to the sub-ECU 32. The control portion 31C maintains the target brake pressure until the vehicle 10 stops. The sub-ECU 32 drives the intake valve 27 and the exhaust valve 28 (see fig. 4) based on the instruction of the target brake pressure from the main ECU 31.

When the main brake is executed, the main ECU31 determines whether or not the abnormality should be ended (step S25). The abnormal handling may be determined to be ended when the vehicle 10 is stopped and the parking brake is actuated, or may be determined to be ended when the ignition switch is turned off, or may be determined to be ended at another timing. When the main ECU31 determines that the response is not completed when abnormality is determined (step S25: no), it continues the main braking while giving the sub ECU32 the target brake pressure (step S24). When the main ECU31 determines that the response has ended when an abnormality is detected (step S25: yes), the process for the response when an abnormality is detected ends.

The main ECU31 operates the in-cabin device 56 and the out-cabin device 57 at a predetermined timing such as a timing of starting execution of the service brake, independently of the case of the abnormality of the air system. This makes it possible to notify the occupant of the vehicle 10 that an abnormality has occurred and also to prompt another vehicle traveling around the vehicle 10 to be noticed.

Next, the procedure of the release processing in the case where the release switch 52 is operated will be described with reference to fig. 7. The processing shown in fig. 7 is started when the operation switch 51 or the passenger seat operation switch 53 is operated and the main ECU31 receives the stop signal.

As shown in fig. 7, the main ECU31 determines whether the release switch 52 is operated (step S31). That is, the main ECU31 determines whether an operation signal is received from the release switch 52. When the main ECU31 determines that the operation signal has not been received from the release switch 52 (step S31: no), the process proceeds to step S33.

On the other hand, when the main ECU31 determines that the operation signal is received from the release switch 52 (step S31: YES), it transmits a brake release instruction to the sub-ECU 32 (step S32). The sub-ECU 32 that has received the release instruction deactivates the intake valve 27 and the exhaust valve 28 to shut off the supply of air from the air tank 12 to the brake chamber 17.

Next, the main ECU31 determines whether the abnormality countermeasure has ended (step S33). When the main ECU31 determines that the response is not completed when abnormality is determined (step S33: no), the process proceeds to step S31. On the other hand, when the main ECU31 determines that the abnormality countermeasure has ended (step S33: YES), the cancellation processing is ended.

Next, a procedure of processing when the command transmitting unit is normal or abnormal will be described with reference to fig. 8 and 9. Fig. 8 is a procedure of processing when the instruction transmitting unit is normal. Fig. 9 is a procedure of processing when the instruction transmitting unit is abnormal.

As shown in fig. 8, when the command transmitting unit is normal, the command device 1 superimposes the superimposed signal on the communication line (step S41). That is, the superimposing circuit 41C superimposes the ac signal on the communication line until the abnormality of the command transmitting unit is detected. Therefore, a signal including the superimposed signal is transmitted from the command device 1 to the valve control device 2 via the communication line.

Then, the valve control device 2 detects a superimposed signal included in the signal transmitted from the command device 1 (step S42). That is, the superimposed signal detection circuit 42C detects the superimposed signal by detecting the ac signal included in the communication line by the voltage detection circuit 42D. When detecting the superimposed signal, the voltage detection circuit 42D determines that the command transmission unit is normal (step S43). When the command transmitter is normal, the sub-ECU 32 controls the pressure control module 20 in accordance with a command from the main ECU 31.

As shown in fig. 9, when the command device detects that the command transmission unit is abnormal (step S51), the command device outputs an abnormal signal to the superimposing circuit 41C (step S52). That is, when the self-diagnosis by the self-diagnosis unit 31E diagnoses that there is an abnormality or a sensor in the device detects an abnormality, the main ECU31 outputs an abnormality signal to the superimposing circuit 41C. The command device 1 stops the superimposition of the superimposition signal (step S53). That is, the superimposing circuit 41C stops superimposing the ac signal on the communication line. Therefore, a signal not including the superimposed signal is transmitted from the command device 1 to the valve control device 2 via the communication line.

Then, since the signal transmitted from the command device 1 via the communication line does not include the superimposed signal, the valve control device 2 does not detect the superimposed signal (step S54). That is, since the communication line does not include the ac signal, the voltage detection circuit 42D of the superimposed signal detection circuit 42C does not detect the superimposed signal. Since the superimposed signal is not detected by the voltage detection circuit 42D, it is determined that the command transmission unit is abnormal (step S55). The voltage detection circuit 42D outputs an emergency instruction to the sub-ECU 32 (step S56). The sub-ECU 32 causes the pressure control module 20 to perform the emergency operation via the drive circuit 32A without responding to the command signal (step S57). That is, the intake valve 27 and the exhaust valve 28 of the pressure control module 20 are in the open position and the closed position, respectively. Therefore, the command system of the air pressure drive type is switched from the system via the brake valve 13 to the system in which air is directly supplied from the air tank 12. Therefore, even if the air pressure signal from the brake valve 13 is not received, the brake chamber 17 can be operated to generate a braking force.

Next, the effects of the first embodiment will be described.

(1) The command device 1 includes a superimposing circuit 41C that transmits the command signal and transmits the specific signal when the command transmitting unit is normal, and transmits the command signal and does not transmit the specific signal when the command transmitting unit is abnormal, and the valve control device 2 includes a superimposing signal detection circuit 42C that detects the specific signal. When the specific signal is detected, the intake valve 27 and the exhaust valve 28 are controlled in accordance with the command signal, and when the specific signal is not detected, the intake valve 27 and the exhaust valve 28 are not controlled in accordance with the command signal. Therefore, the valve control device 2 can grasp the abnormality of the command transmitting unit without separately providing a communication line for transmitting the abnormality. In addition, since the abnormality is transmitted not by software but by a circuit, the reliability of the system is easily ensured.

(2) The superimposing circuit 41C superimposes a specific signal having a frequency band different from the frequency band of the command signal on the communication line when the command transmitting unit is normal, and does not superimpose a specific signal having a frequency band different from the frequency band of the command signal on the communication line when the command transmitting unit is abnormal. Therefore, the superimposed signal detection circuit 42C does not detect a specific signal having a frequency band different from the frequency band of the command signal included in the communication line, and thus can easily detect an abnormality of the command transmitting unit.

(3) Since the signal other than the frequency band of the command signal is removed by the second CMNF42B, the command signal to be transmitted to the communication line can be acquired even if a specific signal of a frequency band different from the frequency band of the command signal is superimposed on the communication line.

(second embodiment)

A second embodiment in which the control system is embodied as a brake control system will be described below with reference to fig. 10 to 15. The control system of this embodiment is different from the first embodiment in the configuration of the communication unit of the first control device and the communication unit of the second control device. Hereinafter, differences from the first embodiment will be mainly described.

Although not shown in fig. 2, the main ECU31 includes a first communication unit 43 that performs CAN communication, as shown in fig. 10. The main ECU31 and the first communication unit 43 function as the command device 3, and the command device 3 calculates the operation command pressures of the intake valve 27 and the exhaust valve 28. Similarly, although not shown in fig. 2, the sub-ECU 32 includes a second communication unit 44 that performs CAN communication. The sub-ECU 32 and the second communication unit 44 are connected to the command device 3 via a communication line, and function as the valve control device 4 that controls the operations of the intake valve 27 and the exhaust valve 28 in accordance with the calculated operation command pressures.

The first communication unit 43 includes a first CAN transceiver circuit 43A and a communication disconnection circuit 43B in this order from the master ECU 31. The first CAN transceiver circuit 43A is connected in series with the communication cut-off circuit 43B.

The first CAN transceiver circuit 43A is identical to the first CAN transceiver circuit 41A. The main ECU31 and the first CAN transceiver circuit 43A function as a command transmitting unit that calculates an operation command pressure and transmits a command signal indicating the operation command pressure to the valve control device 4.

The communication disconnection circuit 43B is a circuit that fixes the voltage of the communication line to a predetermined voltage different from that when the command transmission unit is normal when the command transmission unit is abnormal. That is, as shown in fig. 11, the communication disconnection circuit 43B is a circuit that short-circuits a communication line on the side of a higher voltage to a power supply of a predetermined voltage, for example, 5V. As shown in fig. 12, the communication disconnection circuit 43C may be a circuit that short-circuits the communication line on the high-voltage side to ground. As shown in fig. 13, the communication disconnection circuit 43D may be a circuit for disconnecting or connecting a communication line on the higher voltage side.

As shown in fig. 10, the communication blocking circuit 43B functions as a signal transmission circuit that transmits a command signal to the valve control device via the communication line without transmitting a specific signal different from the command signal to the valve control device 4 when the command transmission unit is normal, and transmits a specific signal to the valve control device 4 via the communication line without transmitting a command signal to the valve control device when the command transmission unit is abnormal. That is, the communication interrupting circuit 43B transmits the command signal to the valve control device 4 via the communication line without connecting the communication line on the side having a higher voltage to the power supply having a predetermined voltage when the command transmitting unit is normal. The predetermined voltage is a voltage that is not normally generated. When the self-diagnosis by the self-diagnosis unit 31E diagnoses the presence of an abnormality or when a sensor in the device detects an abnormality, the main ECU31 outputs an abnormality signal to the communication disconnection circuit 43B. Then, upon receiving the abnormality signal, the communication disconnection circuit 43B connects the communication line on the higher voltage side to the power supply of the predetermined voltage. Therefore, the communication disconnection circuit 43B does not fix the communication line to the predetermined voltage when the main ECU31 is normal, and fixes the communication line to the predetermined voltage when the main ECU31 is abnormal. As a result, the communication disconnection circuit 43B generates different signals when the command transmission unit is normal and when the command transmission unit is abnormal.

The second communication unit 44 includes a second CAN transceiver circuit 44A and a disconnection detection circuit 44B in this order from the sub-ECU 32. The second CAN transceiver circuit 44A is connected in series with the disconnection detection circuit 44B.

The second CAN transceiver circuit 44A is a circuit that transmits a signal to a communication line in the CAN protocol and receives a signal of the communication line. The disconnection detection circuit 44B is a circuit for detecting that the voltage of the communication line is fixed to a predetermined voltage.

The disconnection detection circuit 44B functions as a detection circuit that detects a specific signal from a signal received from the command device 1 via the communication line. The disconnection detection circuit 44B includes a voltage detection circuit 44C. The voltage detection circuit 44C is a circuit that detects the voltage of the communication line on the higher voltage side. That is, the voltage detection circuit 44C can determine whether or not the voltage of the communication line is fixed to the predetermined voltage. When the voltage of the communication line is fixed to a predetermined voltage, the voltage detection circuit 44C determines that the communication line is abnormal, and outputs an emergency command to the sub-ECU 32. The sub-ECU 32 causes the intake valve 27 and the exhaust valve 28 of the pressure control module 20 to perform an emergency operation via the drive circuit 32A. Here, the emergency operation is an operation performed regardless of the command signal. For example, the emergency operation is an operation of stopping the vehicle 10 by driving the intake valve 27 and the exhaust valve 28 and supplying compressed air from the relay valve 25. The emergency operation may be an operation of decelerating the vehicle 10 to a predetermined speed or less without stopping the vehicle 10. The sub-ECU 32 functions as a valve control unit that controls the intake valve 27 and the exhaust valve 28 in accordance with the received command signal when the specific signal is not detected.

Next, a procedure of processing when the command transmitting unit is normal or abnormal will be described with reference to fig. 14 and 15. Fig. 14 is a procedure of processing when the instruction transmitting unit is normal. Fig. 15 is a procedure of processing when the instruction transmitting unit is abnormal.

As shown in fig. 14, when the command transmitting unit is normal, the command device 3 stops the communication disconnection circuit (step S61). That is, the communication disconnection circuit 43B is not connected to a power supply of a predetermined voltage. The communication disconnection circuit 43C is not connected to ground. The communication disconnection circuit 43D is in a connected state. Therefore, a signal of a normal voltage is transmitted from the command device 3 to the valve control device 4.

Then, the valve control device 4 does not detect the predetermined voltage of the signal transmitted from the command device 3 (step S62). That is, the disconnection detection circuit 44B does not detect the predetermined voltage of the communication line by the voltage detection circuit 44C. When the voltage detection circuit 44C does not detect the predetermined voltage, it determines that the command transmission unit is normal (step S63). When the command transmitter is normal, the sub-ECU 32 controls the pressure control module 20 in accordance with the command from the main ECU 31.

As shown in fig. 15, when detecting that the command transmitting unit is abnormal (step S71), the command device 3 outputs an abnormal signal to the communication disconnection circuit 43B (step S72). That is, when the self-diagnosis by the self-diagnosis unit 31E diagnoses that there is an abnormality or a sensor in the device detects an abnormality, the main ECU31 outputs an abnormality signal to the communication disconnection circuit 43B. The command device 3 fixes the voltage of the communication line to a predetermined voltage (step S73). That is, the communication disconnection circuit 43B connects the communication line on the higher voltage side to the power supply of the predetermined voltage. The communication disconnection circuit 43C connects the communication line on the higher voltage side to ground. The communication disconnection circuit 43D disconnects the communication line on the higher voltage side. Therefore, a signal fixed to a predetermined voltage is transmitted from the command device 3 to the valve control device 4 via the communication line.

Then, the valve control device 4 detects a predetermined voltage of a signal transmitted from the command device 3 via the communication line (step S74). That is, since the voltage of the communication line is fixed to the predetermined voltage, the voltage detection circuit 44C of the disconnection detection circuit 44B detects the predetermined voltage. When the voltage detection circuit 42D detects the predetermined voltage, it determines that the command transmission unit is abnormal (step S75). The voltage detection circuit 42D outputs an emergency instruction to the sub-ECU 32 (step S76). The sub-ECU 32 causes the pressure control module 20 to perform an emergency operation via the drive circuit 32A regardless of the presence or absence of a signal from the main ECU31 (step S77). That is, the intake valve 27 and the exhaust valve 28 of the pressure control module 20 are in the open position and the closed position, respectively. Therefore, the command system of the air pressure drive type is switched from the system via the brake valve 13 to the system in which air is directly supplied from the air tank 12. Therefore, even if the air pressure signal from the brake valve 13 is not received, the brake chamber 17 is operated to generate a braking force, and the vehicle 10 can be stopped.

Next, the effects of the second embodiment will be described.

(4) The command device 3 includes a signal transmission circuit that transmits the command signal without transmitting the specific signal when the command transmission unit is normal, and transmits the specific signal without transmitting the command signal when the command transmission unit is abnormal, and the valve control device 4 includes a detection circuit for detecting the specific signal. When the specific signal is not detected, the intake valve 27 and the exhaust valve 28 are controlled in accordance with the command signal. Therefore, the valve control device 4 can grasp the abnormality of the command transmitting portion without separately providing a communication line for transmitting the abnormality. In addition, since the abnormality is transmitted not by software but by a circuit, the reliability of the system is easily ensured.

(5) When the command transmitter is normal, the voltage of the communication line is not fixed to the predetermined voltage, and when the command transmitter is abnormal, the voltage of the communication line is fixed to the predetermined voltage by the communication disconnection circuit 43B. Therefore, the voltage detection circuit 44C detects that the voltage of the communication line is fixed to the predetermined voltage, and can easily detect an abnormality of the command transmission unit.

(6) The communication disconnection circuit 43B can fix the voltage of the communication line to the voltage of the power supply by short-circuiting the communication line to the power supply. The communication disconnection circuit 43C can fix the voltage of the communication line to zero by short-circuiting the communication line to ground. The communication disconnection circuit 43D can fix the voltage of the communication line to zero by disconnecting the communication line. Therefore, the communication disconnection circuit can be selected based on the reference voltage.

(other embodiments)

The above embodiments can be modified and implemented as follows. The above embodiments and the following modifications can be combined and implemented within a range not technically contradictory to each other.

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

In each of the above embodiments, the main ECU31 may receive an on signal and the like from the operation switch 51, the release switch 52, and the passenger seat operation switch 53 via an on-vehicle network such as the CAN 33.

In each of the above embodiments, the driver abnormality response system 50 may include a main switch (not shown) capable of turning on/off the system. By performing a predetermined operation on the main switch or controlling the main switch by a predetermined control device or the like, for example, the operations of the operation switch 51, the release switch 52, and the passenger seat operation switch 53 can be disabled.

In each of the above embodiments, the air pressure circuit 22 drives the air pressure driven relay valve 25 through the intake valve 27 and the exhaust valve 28. Alternatively, a solenoid valve may be provided in the first supply path 23, and the first supply path 23 may be opened and closed by the solenoid valve. In this case, the sub ECU32 controls the solenoid valve provided in the first supply path 23 in accordance with the operation command pressure.

In each of the above embodiments, the air pressure circuit 22 includes the double check valve 36, and the double check valve 36 switches the supply direction of the air according to the air pressure. Instead of the double check valve 36, a solenoid valve that is set to be driven and non-driven by the sub ECU32 may be provided. When the operation switch 51 or the passenger seat operation switch 53 is turned on, the sub-ECU 32 drives (or does not drive) the electromagnetic valve to switch the air supply direction.

In each of the above embodiments, the abnormality coping is performed by the on operation of the operation switch 51 and the passenger seat operation switch 53. Instead of or in addition to the above, a biological detection device that detects the fatigue state or health state of the driver may be used. The biological detection device detects the state of the driver using one or more parameters such as the position, posture, eye state such as eyelids or sight line, pulse, heart rate, and body temperature of the face or head of the driver. In this aspect, the stop signal is transmitted when the biological detection device detects an abnormality of the driver. Alternatively, the ECU mounted on the vehicle may compare the road information with the vehicle state such as the presence or absence of the vehicle speed and the operation of the accelerator pedal or the brake pedal, and transmit the stop signal when the driving abnormality is detected.

In each of the above embodiments, the brake control device is mounted to the vehicle 10 in which the command system for braking is an air pressure circuit in a later-mounted manner, but the brake control device may be mounted to a vehicle in which an EBS is mounted in a later-mounted manner. Further, instead of the rear mounting, a vehicle may be mounted with a driver abnormality response system in advance.

In each of the above embodiments, the driver abnormality handling system is described as being mounted on the vehicle 10 such as a bus. The vehicle may be a truck, a construction machine, or the like, other than a bus. As another aspect, the driver abnormality response system may be mounted on another vehicle such as a passenger car or a railway vehicle.

In each of the above embodiments, the system for responding to a driver's abnormality is applied to the all-air-braked vehicle 10. Not limited to this, the driver abnormality coping system can also be applied to a vehicle having another type of brake system. The pressure control module can be applied to a vehicle having a brake mechanism of an air over hydraulic (air over hydraulic) type. The brake mechanism connects the pressure control module to the plurality of brake boosters via the ABS control valve. The brake booster is for the front wheels, the left rear wheels, and the right rear wheels, and generates braking force for the wheels by increasing the hydraulic pressure in the hydraulic circuit using air pressure. The pressure control module may be applied to a brake mechanism including a brake booster for front wheels, a brake booster for rear wheels, and an ABS control valve provided in a hydraulic circuit.

In each of the embodiments described above, the present invention is applied to a vehicle in which a brake mechanism is controlled by an air pressure circuit. However, the same problem arises in that a driver's abnormality may occur even in a new vehicle or a vehicle in use in which the brake mechanism is controlled by the hydraulic circuit. Therefore, the pressure control module 20 according to each of the embodiments described above may be applied to a vehicle in which a command system for sending a command to a brake mechanism is realized by a hydraulic circuit. In the hydraulic circuit, the pressure control module 20 also operates in the same manner as in the above-described embodiment. In this aspect, the brake mechanism to be controlled may be a mechanism other than the brake chamber. The hydraulic circuit and the air pressure circuit are examples of circuits that are driven in accordance with the pressure of the fluid.

In each of the above embodiments, the self-diagnosis unit 31E is provided in the main ECU31, but the self-diagnosis device 60 may be provided outside the main ECU31 and the

first communication units

41 and 43. In the first embodiment, the self-diagnosis device 60 diagnoses whether or not at least one of the master ECU31, the first CAN transceiver circuit 41A, the first CMNF 41B, and the superimposing circuit 41C is abnormal. In the second embodiment, the self-diagnosis device 60 diagnoses whether or not at least one of the master ECU31, the first CAN transceiver circuit 43A, and the communication disconnection circuit 43B is abnormal.

In the first embodiment, the second communication unit 42 is provided with a superimposing circuit (second signal transmission circuit) for transmitting a state signal indicating the state of the valve to the command device 1 via the communication line and transmitting a specific signal different from the state signal to the command device 1 when the valve control unit is normal, and the first communication unit 41 is provided with a superimposing signal detection circuit (first detection circuit) for detecting the specific signal different from the state signal from the signal received from the valve control device 2 via the communication line, wherein the superimposing circuit transmits the state signal to the command device 1 via the communication line and does not transmit the specific signal to the command device 1 when the valve control unit is abnormal. Further, it is also possible to recognize an abnormality in both directions of the command device 1 and the valve control device 2. In this case, the valve control device 2 transmits a state signal indicating the state of the valve, and transmits a specific signal different from the state signal. The sub-ECU 32 is provided with a self-diagnosis unit or a self-diagnosis device is provided outside the sub-ECU 32 to diagnose whether or not there is an abnormality. The signal transmission circuit of the command device 1 is a first signal transmission circuit, and the detection circuit of the valve control device 2 is a second detection circuit.

In the second embodiment, the second communication unit 44 is provided with the communication disconnection circuit (second signal transmission circuit) that transmits the state signal indicating the state of the valve to the command device 3 via the communication line without transmitting the specific signal different from the state signal to the command device 3 when the valve control unit is normal, and the first communication unit 43 is provided with the disconnection detection circuit (first detection circuit) that transmits the specific signal different from the state signal to the command device 3 via the communication line without transmitting the command signal to the command device 3 when the valve control unit is abnormal. Further, it may be possible to recognize an abnormality in both directions of the command device 3 and the valve control device 4. In this case, the valve control device 4 transmits a state signal indicating the state of the valve, and transmits a specific signal different from the state signal. The sub-ECU 32 is provided with a self-diagnosis unit or a self-diagnosis device is provided outside the sub-ECU 32 to diagnose whether or not there is an abnormality. The signal transmission circuit of the command device 3 is a first signal transmission circuit, and the detection circuit of the valve control device 4 is a second detection circuit.

In the first embodiment, a superimposing circuit and a superimposed signal detection circuit may be provided in each of 3 or more control apparatuses, and the frequency of a signal superimposed on each superimposing circuit may be made different, thereby determining whether or not any of the control apparatuses is abnormal.

In the second embodiment, each of 3 or more control devices may be provided with a communication disconnection circuit and a disconnection detection circuit, and the communication disconnection circuits may be set to different voltages to determine whether or not any of the control devices is abnormal.

In each of the above embodiments, the command device and the valve control device are 1 to 1, and there may be one command device and a plurality of valve control devices. In this case, a superimposing circuit is provided in the command device, a superimposed signal detection circuit is provided in each valve control device, and each valve control device performs an emergency operation when there is an abnormality in the command device. Further, a communication disconnection circuit is provided in the command device, a disconnection detection circuit is provided in each valve control device, and each valve control device performs an emergency operation when there is an abnormality in the command device.

In the first embodiment, the superimposing circuit superimposes the superimposed signal when the command transmitting unit is normal, and stops superimposing the superimposed signal when the command transmitting unit is abnormal. However, the superimposing circuit may stop superimposing the superimposed signal when the command transmission unit is normal and superimpose the superimposed signal when the command transmission unit is abnormal. In this case, the type of abnormality may be determined by changing the frequency of the superimposed signal.

In the first embodiment, the first CMNF 41B and the second CMNF42B may be omitted.

In each of the above embodiments, the first CAN transceiver circuit 41A (43A) and the second CAN transceiver circuit 42A (44A) may be omitted depending on the communication protocol.

In the first embodiment, after the determination of normality or abnormality is made based on the presence or absence of the superimposed signal, an emergency operation is performed. However, the determination of normality and abnormality may be omitted, and an emergency operation may be performed depending on the presence or absence of a superimposed signal.

In each of the above embodiments, the sub-ECU 32 causes the intake valve 27 and the exhaust valve 28 to perform the emergency operation via the drive circuit 32A. However, the detection circuit may directly output the output to the drive circuit 32A to cause the intake valve 27 and the exhaust valve 28 to perform emergency operation.

In each of the above embodiments, the drive circuit 32A for driving the intake valve 27 and the exhaust valve 28 is provided outside the sub-ECU 32, but the drive circuit 32A may be provided inside the sub-ECU 32.

In each of the above embodiments, in addition to the CAN 33, a network such as FlexRay (registered trademark) or Ethernet (registered trademark) may be used as the in-vehicle network. In this case, the abnormality can be detected by superimposing the superimposed signal on the communication line or fixing the voltage of the communication line to a predetermined voltage.

In each of the above embodiments, the present invention is applied to a control system used in a driver-abnormality coping system of a vehicle. However, the present invention may be applied to a control system for controlling a brake device of a railway vehicle, a control system for controlling a door of a railway vehicle, a control system for controlling a hydraulic pump of a construction machine or the like, a control system for controlling a home door device, and the like.

In each of the above embodiments, the plurality of objects may be integrated with each other, and conversely, an object formed of one object may be divided into a plurality of objects. Whether or not they are integrated, they may be configured to achieve the object of the present invention.

In each of the above embodiments, the objects having the plurality of functions distributed may be collectively provided with some or all of the plurality of functions, and conversely, the objects having the plurality of functions collectively provided may be provided so that some or all of the plurality of functions are distributed. Whether the functions are centralized or distributed, the functions may be configured to achieve the object of the present invention.

Description of the reference numerals

1: an instruction device; 2: a valve control device; 3: an instruction device; 4: a valve control device; 10: a vehicle; 11: an air pressure brake system; 12: a gas tank; 13: a brake valve; 13A: a front pressure chamber; 13B: a rear pressure chamber; 13C: a brake pedal; 14A: a protection valve; 14B: an air horn device; 15: a relay valve; 16: an ABS control valve; 17: a brake chamber; 18: an air pipe; 20: a pressure control module; 21: a housing; 21A: a port connection portion; 21D: a protrusion; 22: an air pressure circuit; 23: a first supply path; 24A: a front signal supply path; 24B: a rear signal supply path; 25: a relay valve; 25A: an outlet port; 25B: a pilot port; 26: a branch circuit; 27: a valve for intake air; 27A: wiring; 28: a valve for exhaust; 28A: wiring; 29: a signal supply path; 30: a third supply path; 31: a main ECU; 31E: a self-diagnosis unit; 32: a sub ECU; 32A: a drive circuit; 33: CAN; 35: a first pressure sensor; 37: a front air supply path; 38: a front air supply path; 39: a second pressure sensor; 41: a first communication unit; 41A: a first CAN transceiver circuit; 41B: a first CMNF; 41C: a superimposing circuit; 42: a second communication unit; 42A: a second CAN transceiver circuit; 42B: a second CMNF; 42C: a superimposed signal detection circuit; 42D: a voltage detection circuit; 43: a first communication unit; 43A: a first CAN transceiver circuit; 43B, 43C, 43D: a communication cutoff circuit; 44: a second communication unit; 44A: a second CAN transceiver circuit; 44B: cutting off the detection circuit; 44C: a voltage detection circuit; 50: a driver response system when the driver is abnormal; 51: an operating switch; 52: the switch is released; 53: a passenger seat operation switch; 55: a speed sensor; 56: an in-vehicle device; 57: an outside-compartment device; 58: a discharge unit; 60: a self-diagnostic device.

Claims

1. A control system for controlling a valve that adjusts compressed air supplied to a brake device for generating a braking force in a vehicle, the control system comprising:

a command device that calculates an operation command pressure of the valve; and

a valve control device connected to the command device via a communication line and controlling the operation of the valve in accordance with the calculated operation command pressure,

wherein the command device comprises:

a command transmission unit that calculates the operation command pressure and transmits a command signal indicating the operation command pressure to the valve control device; and

a signal transmission circuit that transmits the command signal and a specific signal different from the command signal to the valve control device via the communication line in a case where the command transmission section is normal, and transmits the command signal to the valve control device via the communication line without transmitting the specific signal to the valve control device in a case where the command transmission section is abnormal,

the valve control device is provided with:

a detection circuit that detects the specific signal from a signal received from the instruction device via the communication line; and

and a valve control unit that controls the valve in accordance with the received command signal when the specific signal is detected, and that does not control the valve in accordance with the command signal when the specific signal is not detected.

2. The control system of claim 1,

the signal transmission circuit superimposes the specific signal having a frequency band different from a frequency band of the command signal on the communication line when the command transmission unit is normal, and does not superimpose the specific signal when the command transmission unit is abnormal,

the detection circuit detects the specific signal superimposed on the communication line.

3. The control system of claim 2,

the valve control device is configured such that a filter for removing a signal other than the frequency band of the command signal is disposed between the detection circuit and the valve control unit.

4. The control system according to any one of claims 1 to 3,

the signal transmission circuit is set as a first signal transmission circuit,

the detection circuit is set as a second detection circuit,

the valve control device includes a second signal transmission circuit that transmits a state signal indicating a state of the valve and a specific signal different from the state signal to the command device via the communication line when the valve control unit is normal, and transmits the state signal to the command device via the communication line without transmitting the specific signal to the command device when the valve control unit is abnormal,

the command device is provided with a first detection circuit that detects a specific signal different from the status signal from a signal received from the valve control device via the communication line.

5. A control system for controlling a valve that adjusts compressed air supplied to a brake device for generating a braking force in a vehicle, the control system comprising:

wherein the command device comprises:

a signal transmission circuit that transmits the command signal to the valve control device via the communication line without transmitting a specific signal different from the command signal to the valve control device in a case where the command transmission section is normal, and transmits the specific signal to the valve control device via the communication line without transmitting the command signal to the valve control device in a case where the command transmission section is abnormal,

the valve control device is provided with:

and a valve control unit that controls the valve in accordance with the received command signal when the specific signal is not detected.

6. The control system of claim 5,

the signal transmission circuit fixes a voltage of the communication line to a predetermined voltage different from a voltage of the communication line in a case where the command transmission unit is normal when the command transmission unit is abnormal,

the detection circuit detects the specific signal by detecting that the voltage of the communication line is fixed to a predetermined voltage.

7. The control system of claim 6,

the signal transmission circuit is any one of a circuit capable of short-circuiting the communication line to a power source when the command transmission unit is abnormal, a circuit capable of short-circuiting the communication line to ground when the command transmission unit is abnormal, and a circuit capable of disconnecting the communication line when the command transmission unit is abnormal.

8. The control system according to any one of claims 5 to 7,

the signal transmission circuit is set as a first signal transmission circuit,

the detection circuit is set as a second detection circuit,

the valve control device includes a second signal transmission circuit that transmits a state signal indicating a state of the valve to the command device via the communication line without transmitting a specific signal different from the state signal to the command device in a case where the valve control portion is normal, and transmits a specific signal different from the state signal to the valve control device via the communication line without transmitting the command signal to the valve control device in a case where the valve control portion is abnormal,