JP2003074606A - Brake for railway rolling stock - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brake for a railway rolling stock capable of stably applying a protection brake or a stay brake using an electro-hydraulic actuator. SOLUTION: The brake is provided with a first passage 41 guiding operating oil delivered from a pump 21 by the normal rotation of a motor 20 to a remitting-side oil chamber 3 and a second passage 42 guiding the operating oil delivered from the pump 21 by the reverse rotation of the motor 20 to a braking-side oil chamber 4 and the operation direction of an output cylinder 71 is switched by switching the delivering direction of the pump 21. The brake is also provided with a third passage 43 guiding the operation oil flowing out from the remitting-side oil chamber 3 to the braking-side oil chamber 4, an ordinarily opened type third solenoid valve 17 interposed on the way to the third passage 43, and a controller 50 closing the third solenoid valve 17 when operating a service brake, while opening the third solenoid valve 17 in operating the protection brake, and driving the motor 20 so as to guide the operating oil delivered from the pump 21 to the braking-side oil chamber 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a railway vehicle brake system, and more particularly to an improvement that enables an appropriate braking operation.

[0002]

2. Description of the Related Art In a railway vehicle brake system, energy saving is achieved by mainly using an electric regenerative brake and a friction type auxiliary brake for pressing a brake shoe against a wheel as an auxiliary.

Generally, as an auxiliary brake of this type,
Air brakes with pneumatic actuators have been used. However, this air brake requires the supply of air pressure to the actuator provided for each wheel, and it is necessary not only to install a complicated pneumatic circuit in the vehicle but also to drive the compressor provided as an air pressure source. Large amount of energy is consumed and it is difficult to save energy.

Further, conventionally, there has been a brake device using hydraulic pressure as described below. A hydraulic actuator is provided for each wheel and supplies hydraulic pressure to each hydraulic actuator from a common hydraulic source. It functions as a service brake used during normal driving and as a safety brake used during a power failure. , A braking device that is adapted to perform the function of a stationary brake that is continuously applied when the vehicle is stationary (Japanese Patent Application Laid-Open No. 2-212058).
000-168535). A brake device (see Japanese Patent Application Laid-Open No. 2001-153164) in which an electric hydraulic actuator is provided for each wheel and the braking force is controlled by switching the discharge direction of a pump driven by an electric motor.

[0005]

However, the braking device (1) needs to supply hydraulic pressure to the actuator provided for each wheel, and not only a complicated hydraulic circuit needs to be provided in the vehicle. The energy consumed to drive the pump provided as a hydraulic pressure source is large, and it is difficult to save energy.

Further, the brake device of (1) uses the accumulator as the energy source during the operation of the safety brake, and the hydraulic circuit is open to the atmosphere. Therefore, the gas enclosed in the accumulator is released to the atmosphere via the hydraulic oil. The pressure accumulated in the accumulator may decrease over time.

On the other hand, in the brake device, it is not necessary to supply air pressure or hydraulic pressure to the actuator provided for each wheel, and energy can be saved. In addition, since the electric hydraulic actuator is composed of a closed circuit, it is possible to prevent the pressure that can be accumulated in the accumulator from decreasing over time.

However, in the above-mentioned brake device, when the spring force of the brake spring is set to a spring force equivalent to the safety brake, the brake spring becomes very large, resulting in an increase in size of the entire device. When the device becomes large, it is difficult to mount the device on the bogie of the vehicle, and thus the bogie needs to be extensively modified.

The present invention has been made in view of the above problems, and provides a railway vehicle brake device capable of stably applying a safety brake or a stationary brake by using an electric hydraulic actuator and achieving a compact size. The purpose is to provide.

[0010]

A first invention is partitioned by a brake spring for pressing a brake shoe against a braking member to urge it, an output cylinder for displacing the brake shoe with respect to the braking member, and a piston of the output cylinder. The loosening-side oil chamber and the braking-side oil chamber, the bidirectional discharge pump driven by the motor, the first passage for guiding the working oil discharged from the pump to the loosening-side oil chamber by the forward rotation of the motor, and the reverse passage of the motor. The present invention is applied to a brake device that includes a second passage that guides hydraulic oil discharged from a pump to a braking-side oil chamber by rotation, and that switches the operating direction of an output cylinder by switching the pumping direction of the pump.

Then, a third passage for guiding the working oil flowing out from the relaxation side oil chamber to the braking side oil chamber, a normally open third electromagnetic valve interposed in the middle of the third passage, and a service brake A control means for closing the third electromagnetic valve during operation and opening the third electromagnetic valve during operation of the safety brake and driving the motor to guide the hydraulic oil discharged from the pump to the oil chamber on the braking side. It was characterized by.

According to a second aspect of the present invention, in the first aspect of the present invention, a first electromagnetic valve interposed in the middle of the first passage, a second electromagnetic valve interposed in the middle of the second passage, The first and second electromagnetic valves are opened, and the first,
A control means for closing the second electromagnetic valve is provided.

A third aspect of the invention is the fuel cell system according to the first or second aspect of the invention, which is connected to an external hydraulic source to introduce pressurized hydraulic oil into the relieving side oil chamber and to transfer the hydraulic oil in the braking side oil chamber to a reservoir tank. It is characterized in that it is provided with means for releasing the stationary brake to be introduced.

A fourth invention is characterized in that, in any one of the first to third inventions, an orifice is provided for imparting resistance to the working oil flowing out from the resolving side oil chamber through the third passage. I decided to do it.

[0015]

According to the first aspect of the present invention, the third passage is opened through the third electromagnetic valve when the safety brake is activated during a power failure of the main power source and the pump is activated by the safety power source to control the hydraulic pressure. Since the configuration is such that it is guided to the braking-side oil chamber, braking torque is generated by the urging force of the brake spring and the hydraulic pressure of the output cylinder. Therefore, it is not necessary to make the spring force of the brake spring the spring force equivalent to the safety brake, and it is possible to prevent the brake spring from increasing the size of the device.

When the stationary brake is actuated, the third passage is opened through the third electromagnetic valve of the normally open type so that the hydraulic oil in the relief side oil chamber flows out from the third passage. Therefore, the braking force is applied by the brake spring. Torque is generated.

Thus, the safety brake and the stationary brake can be stably applied by using the electric hydraulic actuator.

According to the second aspect of the invention, after the softening operation performed by opening the first and second electromagnetic valves and operating the pump is completed, the brake shoe is held in a state of being separated from the wheel at the time of softening holding. By closing the first and second electromagnetic valves, the working hydraulic pressures of the relieving-side oil chamber and the braking-side oil chamber are maintained, so that the operation of the pump can be stopped and labor can be saved.

According to the third aspect of the invention, when the vehicle is towed, for example, when the power source or the motor fails, it is possible to cancel the operation of the stationary brake.

According to the fourth aspect of the invention, since the flow rate of the working oil flowing out from the loosening side oil chamber is adjusted by restricting the orifice, the rising characteristic of the braking torque during the operation of the safety brake can be arbitrarily set.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a system diagram of a railway vehicle braking device. In this brake device, the electro-hydraulic actuator 70 presses the brake shoe 29 against the tread surface (braking member) of the wheel 60 to generate a braking torque. The electric hydraulic actuator 70 applies this pressing force to the brake shoe 29 by the urging force of the brake spring 5 and the hydraulic pressure of the output cylinder 71.

The controller 50 exchanges information with the upper brake system 51 and operates this brake device as an auxiliary to an electric regenerative brake (not shown).
The braking device performs the following braking functions according to operating conditions.・ Regular brake operation: Used for braking the vehicle during normal driving.・ Emergency brake operation: Used to exert the maximum braking torque of the vehicle.・ Safety brake operation: Used when the regular braking system fails due to a power failure.・ Stopping brake operation: Used to prevent rolling of the vehicle during detention.

2 and 3 show a specific structure of the brake device. A body 1 and a piston 2 fixed to the vehicle body constitute a double rod type output cylinder 71. The body 1 functions as a cylinder tube in which the piston 2 is slidably accommodated, and the piston 2 partitions the loosening-side oil chamber 3 and the braking-side oil chamber 4.

A brake spring 5 is compressed and interposed between the body 1 and the inside of the cylindrical piston 2. The spring force of the brake spring 5 is set so that a required braking torque can be obtained when the stationary brake is operated.

The brake spring 5 has a double spring structure composed of coil springs 61 and 62 having different winding diameters. Inside the piston 2, coil springs 61 and 62 are concentrically arranged side by side.

The body 1 has internal and external coil springs 61, 62.
Are formed so as to be offset in the axial direction of the piston 2, and the stepped portion provided between the spring seats 63 and 64 positions the end of the inner coil spring 61 in the radial direction. Similarly, spring seats 65, 66 for the coil springs 61, 62 are formed in the piston 2 with an offset in the sliding axis direction of the piston 2,
The step provided between the spring seats 65 and 66 positions the end of the outer coil spring 62 in the radial direction.
As a result, the coil springs 61 and 62 do not interfere with each other.

A cylindrical jerk rod 6 is slidably provided inside the cylindrical piston 2, and an output pin 9 is connected to the jerk rod 6. The output pin 9 is connected via a shaft 12 to a brake shoe head. 10 and one end of the link 11 are rotatably connected. The other end of the link 11 is rotatably connected to the body 1 via a shaft 73. That is, the link 11 rotatably connects the pendulum head 10 to the body 1 and supports the force exerted by the wheel 60 on the brake shoe 29. A damper mechanism 23 for suppressing relative displacement between the output pin 9 and the brake shoe head 10 is provided.
Is provided.

The base end of the output pin 9 is rotatably connected to the inside of the cylindrical jerk rod 6 via a spheral bearing 8. The output pin 9 is rotated via the spheral bearing 8 as it is displaced in the axial direction, and is inclined with respect to the central axis of the output cylinder 71.

An adjusting mechanism 67 for adjusting the axial position of the output pin 9 with respect to the jerk rod 6 is provided. When the output pin 9 is pushed out by the adjusting mechanism 67 in response to the wear of the brake shoe 29,
The gap of the brake shoe 29 with respect to the tread surface of the wheel 60 can be adjusted.

A jerk spring 7 composed of a plurality of disc springs is interposed between the jerk rod 6 inside the cylindrical piston 2. The spring force of the jerk spring 7 is set to be weaker than the spring force of the brake spring 5. Brake spring 5 is restrained by the spring force of brake spring 2.
When 9 is pressed against the wheel 60, the jerk spring 7 acts as a cushioning member, and the sudden increase in the pressing force during braking is reduced.

A spring seat 68 for the jerk spring 7 is formed annularly in the hollow piston 2. This spring seat 68 is provided for each spring seat 6 with respect to the brake spring 5.
It is formed at a position opposite to 5, 66. Thus, the brake spring 5 and the jerk spring 7 are housed side by side inside the piston 2 so as to sandwich the piston 2. Therefore, the body of the brake device can be made compact, and the brake device can be installed in the interposing space where the conventional pneumatic brake device is provided.

Further, since the brake spring 5 and the like are not arranged around the body 1, the degree of freedom in arranging the oil passage provided in the body 1 is increased and the body 1 is
The electro-hydraulic actuator 70 can be unitized by attaching the manifold block 16 to the side portion of the.

In the manifold block 16, each solenoid valve 17 constituting the electric hydraulic actuator 70,
18, 19, the motor 20, the pump 21, the accumulator 22 and the like are assembled, and a hydraulic circuit connecting them is formed.

The body 1 has a loosening side oil chamber 3 and a braking side oil chamber 4
The pressure sensors 13 and 14 for detecting the pressure are attached respectively. Since the electric hydraulic actuator 70 is provided as a unit in the body 1 and the manifold block 16, it is not necessary to provide hydraulic piping or the like on the vehicle body side, and only electric and signal wirings need to be provided.

FIG. 4 shows a hydraulic circuit of the electric hydraulic actuator 70. This will be described. In the figure, reference numeral 21 denotes a bidirectional discharge type gear type hydraulic pump, and a first bidirectional discharge type hydraulic pump 21 has a discharge port communicating with each of the discharge ports of the release side oil chamber 3 and the braking side oil chamber 4. , The second passage 41,
42 forms a closed circuit with the reservoir tank 22.

Pump 21 driven by forward / reverse rotation motor 20
The operating direction of the output cylinder 71 is switched by switching the rotating direction (discharging direction) of the. During normal rotation of the pump 21 ... The hydraulic oil discharged from the pump 21 flows through the first passage 41 to the relaxation side oil chamber 3, while the hydraulic oil in the braking side oil chamber 4 passes through the second passage 42 and is pumped. 21, the output cylinder 71 contracts, and the brake shoe 29 is separated from the wheel 60. When the pump 21 rotates in the reverse direction ... The hydraulic oil discharged from the pump 21 flows to the braking side oil chamber 4 through the second passage 42, while the hydraulic oil in the loosening side oil chamber 3 passes through the first passage 41 to the pump. 21, the output cylinder 71 extends and separates the brake shoe 29 from the wheel 60.

An orifice 27 is provided in the passage connecting the first and second passages 41 and 42, and the operation of the output cylinder 71 is stabilized by increasing the rotational speed of the motor 20 to a certain extent or more during operation. There is.

Normally-closed first and second electromagnetic valves 19 and 18 are provided in the middle of the first and second passages 41 and 42, respectively. The first and second electromagnetic valves 19 and 18 are switched to the open position where the first and second passages 41 and 42 are opened when they are energized, and the check valves 49 and 4 are opened when they are not energized.
The hydraulic pressure is switched to a closed position via 8 to stop the hydraulic oil from flowing out from the loosening side oil chamber 3 and the braking side oil chamber 4.

The controller 50 controls the first and second electromagnetic valves 1 when the service brake for rotating the pump 21 is activated.
Switch 9 and 18 to the open position.

The controller 50 has a first,
While the second electromagnetic valves 19 and 18 are opened and the pump 21 is rotated, the first and second electromagnetic valves 19 are held at the time of holding the loosening in which the loosening operation is finished and the brake shoe 29 is kept away from the wheel 60. , 18 to the closed position,
The rotation of the pump 21 is stopped. In this way, at the time of holding the loosening solution, the first and second electromagnetic valves 19, 18 are used to make the loosening side oil chamber 3,
Since the operating oil pressure of the braking side oil chamber 4 is maintained, the pump 21
It is possible to stop the operation of and save labor.

The closed circuit of the electric hydraulic actuator is connected to the reservoir tank 22 via a drain passage 45. The drain passage 45 has the first and second check valves 4
It is connected to the first and second passages 41 and 42 via 6, 47. The first and second check valves 46 and 47 are opened and closed in conjunction with each other, and when one opens, the other closes.

When the safety brake is operated and the stationary brake is operated, the hydraulic oil flowing out from the loosening side oil chamber 3 is supplied to the braking side oil chamber 4.
Is provided with a third passage 43, and a normally open third electromagnetic valve 17 is interposed in the middle of the third passage 43. When the third electromagnetic valve 17 is opened, the hydraulic oil flowing out from the relief side oil chamber 3 is the third passage 43 → the drain passage 45 → the check valve 47 → the second passage 42 → the second electromagnetic valve 18 → the braking side oil chamber. It flows in order of 4.

An orifice 26 is provided in the middle of the third passage 43. Since the flow rate of the hydraulic oil flowing out from the loosening side oil chamber 3 is adjusted by the restriction of the orifice 26, the rising characteristic of the braking torque during the operation of the safety brake can be set arbitrarily.

Next, the operation of the electric hydraulic actuator 70 will be described.

When the stationary brake is operated, all of the brake units are de-energized, and the first and second electromagnetic valves 19 and 18 are switched to the closed position, while the third electromagnetic valve 17 is switched to the open position and the third electromagnetic valve 17 is switched to the third position. The passage 43 opens. Brake spring 5
As the piston 2 moves in the braking direction by the urging force of the hydraulic fluid, the working oil in the loosening side oil chamber 3 flows out through the third passage 43 through the third electromagnetic valve 17, while the working oil flows in the second electromagnetic field. Brake side oil chamber 4 through the check valve of valve 18.
Flow into. In this way, the brake shoe 29 is pressed against the wheel 60 by the urging force of the brake spring 5, and a required braking torque is generated when the vehicle stops.

When the brake release operation is received and the release operation command is received from the upper brake system 51, the controller 50 operates in the following order. The controller 50 uses the third electromagnetic valves 17, 18, 19
Energize all to open the first and second passages 41 and 42,
The third passage 43 is closed. The electric motor 20 is operated, and the hydraulic oil discharged from the hydraulic pump 21 is sent to the loosening side oil chamber 3. In response to this hydraulic pressure, the piston 2 moves in the loosening direction against the brake spring 5 and separates the brake shoe 29 from the wheel 60. During the loosening operation, when the pressure P1 in the loosening side oil chamber 3 rises above a predetermined value, the pressure switch 15 is turned on, and the controller 50 activates a display device (not shown) to notify the driver of this loosening working state. The first electromagnetic valve 19 is de-energized to be closed, the operation of the electric motor 20 is stopped, and the pressure P1 of the relief side oil chamber 3 is maintained to maintain the relief state. In this way, at the time of holding the brake 29 in a state of being separated from the wheel 60, the first and second electromagnetic valves 19 and 18 are closed so that the working hydraulic pressures of the releasing side oil chamber 3 and the braking side oil chamber 4 are held. Therefore, the operation of the pump 21 can be stopped, and labor can be saved.

When the regular brake is activated or the emergency brake is activated, when the regular brake braking operation command or the emergency brake braking operation command is received from the upper brake system 51, the controller 50 operates in the following order. The controller 50 uses the third electromagnetic valves 17, 18, 19
Energize all, closing the third passage 43 and closing the first and second passages 4
Open 1, 42. The electric motor 20 is operated, and the hydraulic oil discharged from the hydraulic pump 21 is sent to the braking side oil chamber 4. In response to this hydraulic pressure and the urging force of the brake spring 5, the piston 2 moves in the braking direction and presses the brake shoe 29 against the wheel 60 to generate a braking torque. At this time, the controller 50 feedback-controls the operation of the electric motor 20 so that the pressure difference P2-P1 between the relief side oil chamber 3 and the braking side oil chamber 4 detected by the pressure sensors 13 and 14 rises to a predetermined value or more. .

When the safety brake is activated, when the brake operation command for the safety brake is received from the upper brake system 51, the controller 50 operates in the following order. The controller 50 deenergizes the third electromagnetic valves 17 and 19 and energizes the second electromagnetic valve 18. As a result, the first passage 41 is closed and the third passage 43 and the second passage 42 are opened. The electric motor 20 is operated, and the hydraulic oil discharged from the hydraulic pump 21 is sent to the braking side oil chamber 4. In response to this hydraulic pressure and the urging force of the brake spring 5, the piston 2 moves in the braking direction and presses the brake shoe 29 against the wheel 60 to generate a braking torque. At this time, the hydraulic oil in the loosening side oil chamber 3 flows out through the orifice 26 of the third passage 43, and the rising characteristic of the braking torque is controlled by the orifice 26 and the jerk spring 7.

As described above, the third passage 43 is opened through the third electromagnetic valve 17 when the safety brake is operated during a power failure or the like, and the pump 21 is operated by the safety power source to guide the hydraulic pressure to the braking side oil chamber 4. Because of the configuration, the braking torque is generated by the urging force of the brake spring 5 and the hydraulic pressure of the output cylinder 71. As a result, the brake spring 5
It is not necessary to make the spring force of the spring force equivalent to the safety brake, and the brake spring 5 can prevent the device from becoming large.

Even if the hydraulic pump 21 does not operate due to a failure of the safety power source or the like, the third passage 43 is opened via the normally open third electromagnetic valve 17, and the hydraulic oil in the loosening side oil chamber 3 is opened. Is discharged from the third passage 43, the piston 2 moves due to the urging force of the brake spring 5 to generate a braking torque even when the hydraulic pump 21 does not operate due to a failure of the safety power source or the like. At the time of this power failure, the second electromagnetic valve 18 switches to the closed position,
The hydraulic oil flows into the braking-side oil chamber 4 that opens and expands the check valve 48.

When the vehicle is towed when the power source or the motor 20 fails, it is necessary to cancel the operation of the stationary brake.
In response to this, the hydraulic circuit of the hydraulic actuator 70 is connected to an external hydraulic source to introduce pressurized hydraulic oil into the relieving side oil chamber 3 and to transfer the hydraulic oil in the braking side oil chamber 4 to the reservoir tank 22.
The stationary brake release means introduced in the above is provided. A manual hydraulic power source (manual pump)
A loosening passage (coupler) 81 that connects 80 and guides the hydraulic oil sent from this to the loosening side oil chamber 3, and a loosening passage 81.
Check valve 82 installed in the middle of the
A stop valve 83 that closes the valve 3, a fourth passage 44 that guides the hydraulic oil in the reservoir tank 22 to the braking-side oil chamber 4, and a stop valve 84 that closes the fourth passage 44.

When manually releasing the operation of the stationary brake, the stop valve 83 is closed, the stop valve 84 is opened, and the pressurized hydraulic oil is sent from the manual hydraulic pressure source 80 to the loosening passage 81. The hydraulic fluid thus sent to the loosening passage 81 flows into the loosening side oil chamber 3 through the check valve 82, and moves the piston 2 against the brake spring 5. The hydraulic oil in the braking-side oil chamber 4 that contracts with the movement of the piston 2 flows into the reservoir tank 22 through the manual valve 84.
As a result, the brake shoe 29 is separated from the wheel 60, the operation of the stationary brake is released, and the vehicle can be towed.

As described above, the brake device can stably apply the regular brake, the safety brake, and the stationary brake by using the electric hydraulic actuator 70 and the brake spring 5, while the vehicle is operated when the power source or the motor 20 fails. When pulling, the operation of the stationary brake can be manually released to maintain the relieved state.

It is obvious that the present invention is not limited to the above-mentioned embodiments and various modifications can be made within the scope of the technical idea.

[Brief description of drawings]

FIG. 1 is a system diagram of a brake device showing an embodiment of the invention.

FIG. 2 is a vertical sectional view of the brake device.

FIG. 3 is a lateral cross-sectional view of the braking device.

FIG. 4 is a hydraulic circuit diagram of the electric hydraulic actuator.

[Explanation of symbols]

2 pistons 3 Relief side oil chamber 4 Braking side oil chamber 5 Brake spring 6 jerk cylinder 7 jerk spring 17 Third solenoid valve 18 Second solenoid valve 19 First solenoid valve 26 Orifice 29 brake 41 first passage 42 Second passage 43 Third passage 50 controller 70 Electric hydraulic actuator 71 Output cylinder 81 Relief passage

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tatsuo Ito             2-4-1, Hamamatsucho, Minato-ku, Tokyo World Trade             Center Building Kayaba Industry Co., Ltd. (72) Inventor Tsutomu Suzuki             2-4-1, Hamamatsucho, Minato-ku, Tokyo World Trade             Center Building Kayaba Industry Co., Ltd. (72) Inventor Yasushi Kajiya             2-4-1, Hamamatsucho, Minato-ku, Tokyo World Trade             Center Building Kayaba Industry Co., Ltd. (72) Inventor Kiyoshi Kawaguchi             2-8 38, Mitsumachi, Kokubunji, Tokyo Foundation Law             Human Railway Integrated Technical Research Institute F term (reference) 3J058 AA06 AA13 AA17 AA28 AA37                       BA67 CC03 CC07 CC19 CD03                       CD06 CD09 CD24 FA21

Claims (4)

[Claims] 1. A brake spring for pressing a brake shoe against a braking member to urge the brake shoe, an output cylinder for displacing the brake shoe with respect to the brake member, and a relaxation side oil chamber and a braking side oil chamber partitioned by a piston of the output cylinder. A two-way discharge pump driven by a motor, a first passage for guiding the hydraulic oil discharged from the pump to the relief side oil chamber by the forward rotation of the motor, and a hydraulic oil discharged from the pump by the reverse rotation of the motor. A brake device having a second passage leading to the braking-side oil chamber, wherein the operating direction of the output cylinder is switched by switching the discharge direction of the pump, the operating oil flowing out from the relaxation-side oil chamber to the braking-side oil chamber. And a normally open third solenoid valve installed in the middle of this third passage and this third solenoid valve is closed when the service brake is activated. On the other hand, when the safety brake is actuated, the third electromagnetic valve is opened, and the control means for driving the motor to drive the hydraulic oil discharged from the pump to the braking side oil chamber is also provided. Brake system for vehicles. 2. A first electromagnetic valve interposed in the middle of the first passage, a second electromagnetic valve interposed in the middle of the second passage, and the first and second electromagnetic valves at the time of relieving operation. The brake device for a railway vehicle according to claim 1, further comprising: a control unit that opens the valve and closes the first and second electromagnetic valves when the valve is held in the released state. 3. A non-retained brake release means is provided, which is connected to an external hydraulic source to introduce pressurized hydraulic oil into the relaxation side oil chamber and introduce the hydraulic oil in the braking side oil chamber into a reservoir tank. The railway vehicle brake device according to claim 1 or 2. 4. The railway according to any one of claims 1 to 3, further comprising an orifice for imparting resistance to the hydraulic oil flowing from the loosening-side oil chamber through the third passage. Brake system for vehicles.