JP6099506B2 - Sliding control device - Google Patents

Description

  The present invention relates to a sliding control device used in a vehicle brake system.

  When the vehicle is braked, the adhesion between the wheels and the rails is smaller than the braking force, and there may be a sliding state where the wheels do not rotate and slide on the rails. If a skiing condition occurs, the steering stability of the vehicle is lost and the wheels may be damaged. Therefore, sliding control is performed to detect the sliding of the wheel and weaken the pressure of the control when the sliding occurs to recover the adhesion between the wheel and the rail.

  Generally, in the sliding control, sliding is determined by a sliding detector based on a speed input from a speed sensor that detects the speed of the wheel, and the pressure of the control is adjusted when the vehicle is sliding. For example, sliding control is performed by controlling a slip prevention valve, exhausting air pressure output from a brake control device from a brake cylinder, and adjusting the brake cylinder pressure.

  In the sliding control device, if there is an abnormality in the sliding determination unit or the output unit, the sliding control may be performed even though the wheels and the rail are adhered. In such a case, in order to prevent an appropriate braking force from being obtained, a protection circuit is provided that detects an abnormality of the sliding control device and blocks output to the anti-skid valve.

  For example, the sliding control device for a vehicle disclosed in Patent Document 1 measures the exhaust time and supply time of compressed air from a compressed air supply command signal and an exhaust command signal using a counter. Then, when the supply time is subtracted from the exhaust time and the result becomes equal to or greater than the set value, the protection operation is performed as an abnormal state in which the skiing continues even though the braking force is not applied. .

  In the antilock brake control device of Patent Document 2, a bypass path is provided to bypass the hydraulic pressure control unit for the left and right front wheels of the braking pressure piping system in an emergency. The bypass path has a bypass valve that is normally open and closed during anti-lock control, and the electronic control circuit does not output a pressure reduction command to the hydraulic control units of both front wheels for a certain period of time during anti-lock control. When detected, the bypass valve is opened.

  Patent Document 3 describes an antilock brake control device having a failure detection means. The anti-lock brake control device of Patent Document 3 detects the differential pressure between the master cylinder and the wheel cylinder, and warns if there is a differential pressure when anti-lock control (decompression) is not performed.

JP-A-6-133404 JP-A-2-45251 JP-A-2-41964

  In the vehicle sliding control device of Patent Document 1, a mechanical failure of the sliding prevention valve cannot be detected. For example, when the operation does not change even when the anti-skid valve is electrically turned on / off, especially when the brake pressure is not supplied even when the anti-skid valve is turned off, or when the exhaust operation is continued by the anti-skid valve There is a possibility that pressure from the brake control device is not applied to the brake cylinder and the commanded braking force is not sufficient.

  In the antilock brake control device of Patent Document 2, the bypass valve cannot be opened unless a certain period of time elapses after the brake is operated and the antilock control is applied. Further, in the antilock brake control device of Patent Document 3, no abnormality is known until the brake is operated.

  The present invention has been made in view of the circumstances as described above, and an object of the present invention is to detect an abnormality of the anti-skid valve before issuing a brake command.

In order to solve the above-described problems, a sliding control device according to an aspect of the present invention includes a supply stop valve and a discharge valve , a differential pressure detection unit, an initial loading control unit , a sliding control unit, and a failure determination unit. The supply stop valve and the discharge valve are disposed in a path of the working fluid between the brake control device that supplies the brake pressure of the working fluid to the brake cylinder that operates the brake that brakes the rotation of the wheel and the brake cylinder. The supply stop valve stops the supply of the working fluid from the brake control device to the brake cylinder, and the discharge valve discharges the working fluid from the brake cylinder. The differential pressure detecting unit detects a differential pressure between the pressure of the working fluid between the brake control device and the supply stop valve and the pressure of the working fluid between the supply stop valve and the brake cylinder. The initial loading control unit applies a preload of the working fluid from the brake control device to the brake cylinder within a range in which the control device does not give resistance to the wheel rotation when the wheel rotation is not braked. When the sliding control unit determines that the wheel is sliding based on the rotational speed of the wheel, the sliding control unit closes the supply stop valve and further opens the discharge valve. When the preload was applied by the initial charging control unit with the sliding control unit opening the supply stop valve and closing the discharge valve , the failure judgment unit exceeded the absolute value of the differential pressure. In this case, it is determined that at least one of the supply stop valve and the discharge valve is abnormal.

  According to the present invention, when braking of the rotation of the wheel is not performed, the brake control device applies a preload of the working fluid to the brake cylinder within a range in which the brake does not give resistance to the rotation of the wheel, Since the differential pressure before and after is detected, it is possible to detect an abnormality of the anti-skid valve before issuing a brake command.

It is a block diagram which shows the structural example of the brake device which concerns on Embodiment 1 of this invention. 4 is a flowchart illustrating an example of a failure detection operation according to the first embodiment. It is a block diagram which shows the structural example of the brake device which concerns on Embodiment 2 of this invention. 6 is a flowchart illustrating an example of an operation of detouring according to the second embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

Embodiment 1 FIG.
FIG. 1 is a block diagram illustrating a configuration example of a brake device according to Embodiment 1 of the present invention. The brake device includes a brake control device 5, a sliding control device 1, a brake cylinder 4, and a wheel restrictor 3. Further, the output of the rotational speed sensor 6 attached to the wheel 2 is taken into the sliding control device 1. The sliding control device 1 includes a sliding control unit 11, a supply stop valve 12, a discharge valve 13, a differential pressure detection unit 14, a failure determination unit 15, and an initial loading control unit 16. In FIG. 1, a thick solid line indicates the path of the working fluid. The broken line indicates the path of the electric signal.

  Although not shown in FIG. 1, a brake command from the cab is input to the brake control device 5. The value of the load applied to the vehicle is input to the brake control device 5 from the suspension pressure sensor. The brake control device 5 calculates a necessary braking force from the brake command and the vehicle load, and supplies the brake cylinder 4 with the brake pressure of the working fluid corresponding to the brake force. The brake cylinder 4 to which the brake pressure is supplied presses the brake wheel 3 against the wheel 2 to generate a braking force.

  The brake control device 5 includes, for example, a brake control unit, a brake control valve, a relay valve, and the like (all not shown). The brake control valve includes an electromagnetic valve that supplies air as a working fluid to the relay valve, and an electromagnetic valve that discharges air from the relay valve. These solenoid valves are controlled by a brake control unit. The brake control unit controls the brake control valve so that the pressure on the output side of the brake control valve and the relay valve becomes a pressure corresponding to the commanded braking force. The relay valve amplifies the air pressure input from the brake control valve side and supplies it to the brake cylinder 4. That is, the pressure of the air supplied from the relay valve to the brake cylinder 4 is adjusted in proportion to the pressure on the output side of the brake control valve.

  In the sliding control device 1, a supply stop valve 12 is disposed in the working fluid path from the brake control device 5 to the brake cylinder 4. A discharge valve 13 is connected between the supply stop valve 12 and the brake cylinder 4. The supply stop valve 12 and the discharge valve 13 together constitute a slip prevention valve. While the sliding control unit 11 determines that the vehicle is not sliding, the supply stop valve 12 is normally open and the discharge valve 13 is closed, so that the brake pressure from the brake control device 5 remains in the brake cylinder 4 as it is. Supplied.

  When the sliding control unit 11 determines that the wheel 2 is sliding from the output of the rotational speed sensor 6, the sliding control unit 11 operates the supply stop valve 12 and the discharge valve 13 to perform sliding control. For example, when it is determined that the vehicle is sliding, first, the supply stop valve 12 is closed, the brake pressure at that time is maintained, and no further brake pressure is applied. If the adhesion between the wheel 2 and the rail still does not tend to recover, the exhaust valve 13 is further opened to reduce the brake pressure applied to the brake cylinder 4 and to reduce the pressure between the control 3 and the wheel 2. Let When the sliding control device 1 determines that the sliding state has been eliminated, it closes the discharge valve 13, opens the supply stop valve 12, and supplies the brake pressure to the brake cylinder 4 again.

  In the sliding control device 1 according to the first embodiment, the differential pressure is applied to the working fluid path between the brake control device 5 and the supply stop valve 12 and the working fluid path between the supply stop valve 12 and the brake cylinder 4. The detection unit 14 is connected. The differential pressure detector 14 includes a sensor that detects the pressure of the working fluid, and the pressure of the working fluid between the brake control device 5 and the supply stop valve 12 and the working fluid between the supply stop valve 12 and the brake cylinder 4. Detects the differential pressure from the pressure. The differential pressure detection unit 14 inputs the detected differential pressure to the failure determination unit 15.

  Further, the failure determination unit 15 branches and captures the output from the sliding control unit 11 to the sliding prevention valves (the supply stop valve 12 and the discharge valve 13). The failure determination unit 15 determines that the anti-skid valve is abnormal when the absolute value of the differential pressure output from the differential pressure detection unit 14 exceeds a predetermined value when the anti-skid control unit 11 does not operate the anti-skid valve. Judge that there is.

  The failure determination unit 15 also monitors the output from the sliding control unit 11 to the sliding prevention valve. For example, when the operation time of the sliding prevention valve continues beyond a preset time, the sliding control unit 11 or the rotation speed is monitored. It is determined that the sensor 6 or the like is abnormal. In that case, the failure determination unit 15 opens the switch 20 to block the output from the sliding control unit 11 to the sliding prevention valve.

  The initial loading control unit 16 of the sliding control device 1 causes the brake control device 5 to apply the preload of the working fluid from the brake control device 5 to the brake cylinder 4 within a range in which the control 3 does not give resistance to the rotation of the wheel 2. Command. Even when there is no brake command from the driver's cab and braking of the rotation of the wheel 2 is not performed, the brake controller 5 does not give resistance to the rotation of the wheel 2 by the command from the initial loading control unit 16. In the range, a preload of the working fluid is applied to the brake cylinder 4.

  Therefore, the differential pressure detector 14 can detect the differential pressure even when the rotation of the wheel 2 is not braked. The failure determination unit 15 can detect an abnormality of the anti-skid valve before issuing a brake command.

  If the failure determination unit 15 determines that the anti-skid valve is abnormal, the failure determination unit 15 outputs an alarm notifying the driver's cab (not shown) of the abnormality of the anti-skid valve, for example. In the cab, the abnormality of the anti-skid valve is displayed. A crew member who knows the abnormality of the anti-skid valve can continue driving the vehicle within a range of speed at which the abnormal wheel 2 can be safely stopped even if the braking force is not applied to the abnormal wheel 2.

  FIG. 2 is a flowchart illustrating an example of a failure detection operation according to the first embodiment. When the operation of the vehicle is started, the initial loading control unit 16 of the sliding control device 1 instructs the brake control device 5 to apply a preload to the brake cylinder 4. The brake control device 5 applies a preload of the working fluid to the brake cylinder 4 within a range in which the control device 3 does not give resistance to the rotation of the wheel 2 (step S11).

  The failure determination unit 15 checks whether or not the anti-skid valve is output so as to operate. If the anti-skid valve is operated (step S12; YES), the failure determination unit 15 waits until the operation stops. When the anti-skid valve is not actuated (step S12; NO), the differential pressure detection unit 14 detects the differential pressure (step S13). If there is no differential pressure (if the absolute value of the differential pressure does not exceed a predetermined value) (step S14; NO), the process returns to step S12 to check whether the anti-skid valve is activated.

  If there is a differential pressure (when the absolute value of the differential pressure exceeds a predetermined value) (step S14; YES), it is determined that the anti-skid valve is abnormal (step S15).

  As described above, in the sliding control device 1 according to the first embodiment, when the braking of the rotation of the wheel 2 is not performed, the brake control device 3 operates to the brake cylinder 4 within a range that does not give resistance to the rotation of the wheel 2. The pressure difference before and after the anti-skid valve (supply stop valve 12) is detected in a state where the preload of the fluid is applied and the anti-skid valve is not operated. Thereby, the abnormality of the anti-skid valve can be detected before issuing the brake command.

  In the first embodiment, the case where the working fluid is air has been mainly described. The sliding control device 1 according to the first embodiment can also be applied to a brake device that operates with hydraulic pressure in which the working fluid is liquid.

Embodiment 2. FIG.
FIG. 3 is a block diagram showing a configuration example of a brake device according to Embodiment 2 of the present invention. In the second embodiment, when an abnormality of the slip prevention valve is detected, the brake pressure of the working fluid is supplied from the brake control device 5 to the brake cylinder 4 by bypassing the slip prevention valve. The sliding control device 1 according to the second embodiment includes a detour path 17, a detour valve 18, and a double check valve 19 in addition to the configuration of the first embodiment. And the switch 20 which interrupts | blocks the command from the sliding control part 11 to a sliding prevention valve is not provided. Other configurations are the same as those in the first embodiment.

  In the second embodiment, a bypass path 17 that reaches the brake cylinder 4 from the middle of the path of the working fluid from the brake control device 5 to the supply stop valve 12 is provided. A bypass valve 18 is arranged in the middle of the bypass path 17. The route passing through the supply stop valve 12 and the bypass route 17 are connected to the inflow side of the double check valve 19. The outflow side of the double check valve 19 is connected to the brake cylinder 4.

  The bypass valve 18 is closed when the anti-skid valve is normal. In that case, the pressure of the working fluid is supplied from the brake control device 5 to the brake cylinder 4 via the supply stop valve 12. If the failure determination unit 15 determines that the anti-skid valve is abnormal, the failure determination unit 15 opens the bypass valve 18. The brake pressure is supplied from the brake control device 5 to the brake cylinder 4 via the bypass path 17.

  The double check valve 19 circulates the working fluid from the higher pressure on the two inflow sides to the outflow side. When the bypass valve 18 is closed, the working fluid flows from the supply stop valve 12 to the brake cylinder 4, and the working fluid does not flow from the supply stop valve 12 and the brake cylinder 4 to the bypass valve 18. When the bypass valve 18 is open, the working fluid flows from the bypass valve 18 to the brake cylinder 4, and no working fluid flows from the bypass valve 18 and the brake cylinder 4 to the supply stop valve 12 and the discharge valve 13.

  Therefore, when the bypass valve 18 is open, the supply stop valve 12 and the discharge valve 13 are disconnected from the working fluid path. Then, the brake pressure from the brake control device 5 is supplied to the brake cylinder 4 as it is, and the restrictor 3 acts according to the brake command.

  Similar to the first embodiment, the initial charging control unit 16 performs brake control so that the brake fluid is applied to the brake cylinder 4 from the brake control device 5 within a range in which the controller 3 does not give resistance to the rotation of the wheel 2. Command device 5. Even when there is no brake command from the driver's cab and braking of the rotation of the wheel 2 is not performed, the brake controller 5 does not give resistance to the rotation of the wheel 2 by the command from the initial loading control unit 16. In the range, a preload of the working fluid is applied to the brake cylinder 4.

  The failure determination unit 15 is the same as in the first embodiment when the absolute value of the differential pressure output from the differential pressure detection unit 14 exceeds a predetermined value in a state where the sliding control unit 11 does not operate the anti-skid valve. In addition, it is determined that the anti-skid valve is abnormal. Further, for example, when the operating time of the anti-skid valve continues beyond a preset time, it is determined that the anti-skid control unit 11 or the rotational speed sensor 6 is abnormal.

  The failure determination unit 15 opens the bypass valve 18 when determining that the anti-skid valve is abnormal or when determining that the anti-skid control unit 11 or the rotational speed sensor 6 is abnormal. . Therefore, even if any of the gliding control unit 11, the rotation speed sensor 6 or the gliding prevention valve is abnormal, the brake pressure is supplied to the brake cylinder 4 via the detour path 17, and the control 3 operates according to the brake command. To do. In particular, the failure determination unit 15 detects the abnormality of the anti-skid valve and opens the bypass valve 18 before issuing the brake command, so that it is possible to avoid delaying the brake operation from the brake command.

  The failure determination unit 15 outputs an alarm notifying the driver's cab (not shown) of an abnormality in the sliding control in the case of any abnormality in the sliding control unit 11, the rotation speed sensor 6, or the sliding prevention valve. In the cab, the gliding control abnormality is displayed. The crew can recognize that no sliding control is performed on the wheel 2.

  FIG. 4 is a flowchart illustrating an example of a failure detour operation according to the second embodiment. In the flowchart of FIG. 4, an operation of opening the bypass valve 18 is added at the end of the operation of FIG. The failure determination unit 15 first closes the bypass valve 18 (step S20). Thereafter, the operation is the same as in the first embodiment. The operations in steps S21 to S25 are the same as the operations in steps S11 to S15 in FIG. If the failure determination unit 15 determines that the anti-skid valve is abnormal (step S25), the failure determination unit 15 opens the bypass valve 18 (step S26).

  Although not shown in FIG. 4, the failure determination unit 15 also determines abnormalities such as the sliding control unit 11 or the rotation speed sensor 6, and also opens the bypass valve 18 when determining that these are abnormal. As in the first embodiment, the anti-skid valve is not involved in the braking operation when the gliding control unit 11 or the like is abnormal. When the bypass path 17, the bypass valve 18, and the double check valve 19 are provided, it is not necessary to provide the switch 20.

  As described above, in the sliding control device 1 of the second embodiment, in addition to the operation of the first embodiment, when it is determined that the anti-skid valve is abnormal, the brake cylinder 4 bypasses the anti-skid valve. Apply brake pressure to Thereby, it is possible to avoid delaying the brake operation when the anti-skid valve is abnormal.

  DESCRIPTION OF SYMBOLS 1 Sliding control device, 2 wheels, 3 Control, 4 Brake cylinder, 5 Brake control device, 6 Rotational speed sensor, 11 Sliding control part, 12 Supply stop valve (sliding prevention valve), 13 Discharge valve (sliding prevention valve), 14 differential pressure detection unit, 15 failure determination unit, 16 initial loading control unit, 17 bypass route, 18 bypass valve, 19 double check valve, 20 switch.

Claims (2)

A brake control device that supplies a brake pressure of a working fluid to a brake cylinder that operates a brake member that brakes rotation of a wheel, and is disposed in a path of the working fluid between the brake cylinder and the brake control device; A supply stop valve for stopping the supply of the working fluid to the brake cylinder, and a discharge valve for discharging the working fluid from the brake cylinder;
A differential pressure detector that detects a differential pressure between the pressure of the working fluid between the brake control device and the supply stop valve and the pressure of the working fluid between the supply stop valve and the brake cylinder;
An initial charge control unit that applies a preload of the working fluid from the brake control device to the brake cylinder in a range in which the brake does not give resistance to the rotation of the wheel when braking of the rotation of the wheel is not performed;
When it is determined that the wheel is sliding based on the rotation speed of the wheel, a sliding control unit that closes the supply stop valve and further opens the discharge valve;
The absolute value of the differential pressure exceeds a predetermined value when the preload is applied by the initial charging control unit with the sliding control unit opening the supply stop valve and closing the discharge valve. A failure determination unit that determines that at least one of the supply stop valve and the discharge valve is abnormal,
A sliding control device comprising: A bypass path that bypasses the supply stop valve and the discharge valve and supplies the working fluid from the brake control device to the brake cylinder;
A bypass valve that is disposed in the bypass path and switches between the flow and blocking of the working fluid in the bypass path;
With
When the failure determination unit determines that at least one of the supply stop valve and the discharge valve is abnormal, the bypass valve is opened and the brake control device passes through the bypass path to the brake cylinder. The sliding control device according to claim 1, wherein the working fluid is circulated.

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