Brake cylinder device and brake system

Abstract

The present invention provides a brake cylinder device and a brake system capable of preventing the release of the braking force of a spring brake from being reset due to the fluid supplied to the fluid brake after the braking force of the spring brake is released. The brake cylinder device (250) includes: a fluid brake (260) that generates a braking force due to the supply of compressed air; a spring brake (270) that is independent of the fluid brake and generates a braking force by discharging compressed air; and a brake release mechanism (290) that is used to release the braking force of the spring brake and supplies compressed air to the spring brake in order to reduce the braking force of the spring brake when the fluid brake is in effect. The brake cylinder device includes a proportional pressure reducing valve (11) that is used to limit the pressure of the compressed air supplied to the spring brake to a predetermined pressure or less when the braking force of the spring brake is released by the brake release mechanism.

Description

Technical Field

[0001] The present invention relates to a brake cylinder device and a brake system capable of actuating two different brakes, namely a fluid brake and a spring brake. Background Art

[0002] For example, in the braking device for railway vehicles, there is a known brake cylinder device that can activate both a fluid brake and a spring brake (parking brake). The fluid brake is used during normal driving and is activated by compressed air, while the spring brake (parking brake) is used when the vehicle is parked for a long time and is activated by spring force even without compressed air (for example, refer to Patent Documents 1 and 2).

[0003] exist Figure 8 This conventional brake cylinder device 250, an overview of which is shown in FIG. , has a fluid brake 260, which includes a first pressure chamber 264, a first piston 261, a first spring 266, and a rod driving portion 251 as an output member. The fluid brake 260 generates a fluid braking force by supplying compressed air from the first air source 104 to the first pressure chamber 264 via the first port 63. In addition, the brake cylinder device 250 also has a spring brake 270, which includes a second pressure chamber 274, a second piston 271, and a second spring 276. The spring brake 270 generates a braking force (parking braking force) by the second spring 276 pushing the second piston 271 and the shaft 282 as the compressed air in the second pressure chamber 274 is discharged. Among them, Figure 8 Indicates that the spring brake 270 is in an actuating state. In addition, regarding the spring brake 270, there is also known a spring brake that suppresses the action of the spring brake 270 by supplying compressed air from a second air source 106 different from the first air source 104 to the second pressure chamber 274 via the second port 73, and a double check valve is provided in the supply path of the compressed air (Figure 2 of Patent Document 2). When compressed air is not supplied from the second air source 106 to the supply path, the compressed air from the first air source 104 is supplied to the first pressure chamber 264 and is also supplied to the second pressure chamber 274 via the double check valve 108. Thus, such an undesirable situation is prevented from occurring: when the fluid brake 260 is actuated, the spring brake 270 is also actuated at the same time, resulting in excessive braking force.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2004 / 162960

[0007] Patent Document 2: Japanese Patent Application Laid-Open No. 63-125834 Summary of the invention

[0008] Problem that the invention aims to solve

[0009] In addition, Figure 8 The above-described conventional brake cylinder device 250 is equipped with a brake release mechanism 290 that releases the spring brake 270 (parking brake) during operation to allow the fluid brake 260 to be used, thereby releasing the braking force of the spring brake 270 .

[0010] The brake release mechanism 290 includes a lock lever 291 which is a restriction portion for restricting the rotation of the latch wheel 286 and is used to manually release the restriction on the rotation of the latch wheel 286. In the case of the brake release mechanism 290, the restriction of the lock lever 291 is released by operating the lock lever 291 and the relative displacement between the shaft 282 and the second piston 271 is allowed, thereby releasing the braking force of the spring brake 270. In addition, the brake release mechanism 290 restricts the rotation of the latch wheel 286 when the operation of the lock lever 291 is released. In addition, by supplying compressed air to the second pressure chamber 274 until the position of the second piston 271 relative to the shaft 282 is restored, the cylindrical member 285 is rotated and the position of the shaft 282 relative to the second piston 271 is restored.

[0011] If the braking force of the spring brake 270 is released, for example when the vehicle is running empty, and the vehicle is operated without supplying compressed air to the second pressure chamber 274, and compressed air is supplied to the second pressure chamber 274 from the first air source 104 via the double check valve 108, the second piston 271 is pushed in the anti-braking direction, and the spring brake 270 begins to reset, thereby achieving a state in which the spring brake 270 is in effect after the compressed air in the fluid brake 260 is discharged.

[0012] In addition, if Fig. 9 As shown, the brake cylinder device 350 (brake unit 300) having a compound check valve built into the housing also has the same problem. In the brake cylinder device 350, the valve core 301 provided in the housing of the brake cylinder device 350 functions as a movable compound check valve. When the pressure of the compressed air supplied to the first port 63 is greater than the pressure of the compressed air supplied to the second port 73, the valve core 301 is in a state where the first port 63 and the second pressure chamber 274 are connected via the first pressure chamber 264 (solid line). On the other hand, when the pressure of the compressed air supplied to the second port 73 is greater than the pressure of the compressed air supplied to the first port 63, the valve core 301 is in a state where the second port 73 and the second pressure chamber 274 are connected (dashed line).

[0013] The present invention has been made in view of such actual circumstances, and an object of the present invention is to provide a brake cylinder device and a brake system that can prevent the release of the braking force of the spring brake from being reset due to fluid supplied to the fluid brake after the braking force of the spring brake is released.

[0014] Solutions for solving problems

[0015] A brake cylinder device for solving the above-mentioned problem comprises: a fluid brake which generates a braking force by supplying a fluid; a spring brake which is independent of the fluid brake and generates a braking force by discharging the fluid; and a release portion which is used to release the braking force of the spring brake and to supply the fluid to the spring brake in order to reduce the braking force of the spring brake when the fluid brake is in effect, wherein the brake cylinder device comprises a restriction portion which is used to limit the pressure of the fluid supplied to the spring brake to a predetermined pressure or less when the braking force of the spring brake is released by the release portion.

[0016] According to the above configuration, the pressure of the fluid supplied to the spring brake is limited by the limiting portion, so that the braking force of the spring brake can be prevented from being reset after the braking force of the spring brake is released by the releasing portion due to the compressed air supplied to the fluid brake.

[0017] In the brake cylinder device described above, it is preferable that the restricting portion is a pressure control valve that controls the pressure of the fluid to be lower than a pressure that restores the spring brake whose braking force is released by the releasing portion.

[0018] According to the above structure, the fluid supplied to make the fluid brake work is controlled by the pressure control valve to be lower than the pressure for restoring the spring brake, and then supplied to the spring brake. Therefore, it is possible to avoid the release of the braking force of the spring brake caused by the fluid supplied to make the fluid brake work after passing through the release portion and releasing the braking force of the spring brake and resetting it.

[0019] In the above brake cylinder device, it is preferable that the pressure control valve is a proportional pressure reducing valve that reduces the pressure of the fluid at a certain ratio.

[0020] According to the above configuration, the pressure of the fluid supplied to activate the fluid brake can be reduced at a constant rate by the proportional pressure reducing valve, and the fluid can be supplied to the spring brake.

[0021] In the above brake cylinder device, it is preferable that the pressure control valve is a pressure limiting valve that limits the pressure of the fluid to be equal to or lower than the predetermined pressure.

[0022] According to the above configuration, the pressure of the fluid supplied to activate the fluid brake can be limited to a predetermined pressure by the pressure limiting valve, and the fluid can be supplied to the spring brake.

[0023] For the brake cylinder device, it is preferred that the brake cylinder device includes a compound check valve, which supplies the higher pressure of the fluid supplied to the fluid brake and the fluid supplied to the spring brake to the spring brake, and the pressure control valve is located closer to the pressure source side for supplying the fluid to the fluid brake than the compound check valve. According to the above structure, the fluid can be supplied to the compound check valve after the pressure of the fluid supplied to the fluid brake is controlled to be lower than the pressure for restoring the spring brake.

[0024] A brake system for solving the above problem is provided in a railway vehicle having a vehicle body mounted on a chassis, wherein a plurality of the brake cylinder devices are connected in parallel to the limiting portion, wherein the limiting portion is arranged on the vehicle body, and the limiting portion and the brake cylinder device are connected in units of the vehicle body.

[0025] According to the above configuration, since the brake system is provided with the restricting portion on the vehicle body on the upstream side of each brake cylinder device, the restricting portion is not required in each brake cylinder device.

[0026] In the above brake system, preferably, a throttle is provided on the vehicle body side downstream of the restriction portion. According to the above structure, when the connecting pipe connecting the vehicle body and the underframe is broken, the throttle can delay the release of fluid from the broken portion.

[0027] A brake system for solving the above problem is provided in a railway vehicle having a vehicle body mounted on a chassis, wherein a plurality of the brake cylinder devices are connected in parallel to the limiting portion, wherein the limiting portion is arranged on the chassis, and the limiting portion and the brake cylinder device are connected in units of the chassis.

[0028] According to the above configuration, since the brake system is provided with the restricting portion on the underframe on the upstream side of each brake cylinder device, the restricting portion is not required in each brake cylinder device.

[0029] Effects of the Invention

[0030] According to the present invention, after the braking force of the spring brake is released, it is possible to prevent the release of the braking force of the spring brake from being reset due to the fluid brake. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a diagram showing a configuration of a unit brake having a brake cylinder device in a first embodiment of the brake cylinder device.

[0032] Figure 2 It is a diagram showing a state of braking force applied to the spring brake of the brake cylinder device according to the embodiment.

[0033] Figure 3 This is a diagram showing a second embodiment in which a pressure limiting valve is provided in a supply path for supplying compressed air to a brake cylinder device.

[0034] Figure 4 It is a diagram showing a third embodiment of a brake system in which a valve device is provided on a chassis of a vehicle.

[0035] Figure 5 It is a diagram showing a fourth embodiment of a brake system in which a valve device is provided on a vehicle body.

[0036] Figure 6 It is a diagram showing a modified example of a brake system in which a valve device is provided on a chassis of a vehicle.

[0037] Figure 7 It is a diagram showing a modified example of a brake system in which a valve device is provided on a vehicle body.

[0038] Figure 8 It is a diagram showing the structure of a unit brake having a conventional brake cylinder device.

[0039] Fig. 9 It is a diagram showing the structure of a unit brake having a conventional brake cylinder device.

[0040] Description of Reference Numerals

[0041] 1. First supply path; 2. Second supply path; 3. Third supply path; 4. First air source; 5. Fluid brake control device; 6. Second air source; 7. Spring brake control solenoid valve; 8. Compound check valve; 10. Valve device; 11. Proportional pressure reducing valve; 12. Pressure limiting valve; 13. Pressure limiting spring; 15. Throttle; 200. Unit brake; 220. Rod; 221. Rod support; 222. Inner shell; 223. Outer shell; 224. Fixed roller; 225. Movable roller; 226. Return spring; 230. Brake pad support; 250. Brake cylinder device; 251. Rod drive unit; 260. Fluid brake; 261. First piston; 262. 1st cylinder; 264, 1st pressure chamber; 266, 1st spring; 270, spring brake; 271, 2nd piston; 272, 2nd cylinder; 274, 2nd pressure chamber; 276, 2nd spring; 280, bulkhead; 281, through hole; 282, shaft; 284, external thread; 285, cylindrical member; 286, latch wheel; 286A, flange; 287, spring; 290, brake release mechanism; 291, locking rod; 300, brake unit; 301, valve core; 350, brake cylinder device; B, vehicle body; BC, brake chamber; EX, exhaust port; PA, PB, PC, connection port; H, HP, air pipe; T, chassis; V, vehicle; W, wheel. DETAILED DESCRIPTION

[0042] (First embodiment)

[0043] Below, refer to Figure 1 and Figure 2 A first embodiment in which the brake cylinder device is embodied as a unit brake will be described. The brake cylinder device is provided with a valve device.

[0044] <Overall Structure of Unit Brake 200>

[0045] Figure 1 The unit brake 200 shown is configured as a brake device for a railway vehicle. The unit brake 200 brakes the rotation of the wheel W of the vehicle by making the brake pad 31 abut against the wheel W of the vehicle. The unit brake 200 includes: a brake cylinder device 250 for driving a rod driving part 251; a rod 220 that can move forward and backward according to the movement of the rod driving part 251; and a brake pad support 230 installed at the top end of the rod 220, and the brake pad 31 is installed on the brake pad support 230.

[0046] <Rod 220>

[0047] The rod 220 is movably supported by a rod support portion 221 provided at the lower portion of the brake cylinder device 250. The rod 220 is provided to extend in a direction orthogonal to the axle direction of the wheel W of the vehicle. The rod support portion 221 includes an inner housing 222, an outer housing 223, a fixed roller 224, a movable roller 225, and a return spring 226.

[0048] The inner housing 222 is provided on the outer periphery of the base end side of the rod 220 and is a cylindrical member having a thread groove formed on the inner periphery for threading with the external thread formed on the outer periphery of the rod 220. Thus, the protrusion amount of the rod 220 relative to the inner housing 222 can be adjusted.

[0049] The outer housing 223 is a structure in which two cylindrical members are connected, and is provided on the outer periphery of the inner housing 222. The inner housing 222 is rotatable in the outer housing 223. The outer housing 223 is supported relative to the rod support 221 so as to be movable in a direction parallel to the axial direction of the rod 220.

[0050] The fixed roller 224 is a cylindrical roller rotatably supported by the rod support portion 221. The movable roller 225 is a cylindrical roller rotatably supported by the outer housing 223, and moves together with the outer housing 223.

[0051] One end of the return spring 226 is fixed to the rod support portion 221. The other end of the return spring 226 is fixed to the outer housing 223. That is, the return spring 226 urges the outer housing 223 in the axial direction of the rod 220 in the direction (arrow Y2 direction) away from the wheel W. Therefore, if the drive of the rod drive portion 251 is released, the rod 220 moves in the anti-braking direction (arrow Y2 direction) under the action of the return spring 226.

[0052] <Brake cylinder device 250>

[0053] The axial direction of the brake cylinder device 250 is set to extend in a direction substantially orthogonal to the direction in which the rod 220 extends, and is set to extend in the up-down direction of the vehicle. The brake cylinder device 250 moves the rod 220 by moving the rod driving part 251 in the axial direction. The rod driving part 251 is a wedge-shaped member whose width becomes wider as it moves from the top end to the base end, and abuts against the movable roller 225. When the rod driving part 251 moves to the rod support part 221 side, the rod 220 is moved in the braking direction (arrow Y1 direction) with the help of the movable roller 225 and the outer shell 223. On the other hand, when the rod driving part 251 moves in the direction away from the rod support part 221, that is, the anti-braking direction (arrow Z2 direction), the rod 220 moves in the anti-braking direction (arrow Y2 direction) under the action of the return spring 226.

[0054] The brake cylinder device 250 includes a fluid brake 260 for decelerating or stopping a moving vehicle, a spring brake 270 used when the vehicle is parked, and a brake release mechanism 290. The fluid brake 260 and the spring brake 270 are configured to operate the same rod drive unit 251. The brake release mechanism 290 corresponds to a release unit.

[0055] <Fluid brake 260>

[0056] The fluid brake 260 is operated by compressed air as a fluid. The fluid brake 260 has a first piston 261 connected to the rod driving portion 251. The first pressure chamber 264 and the first spring 266 act on the first piston 261 in opposite directions. In the fluid brake 260, the first piston 261 (rod driving portion 251) overcomes the force of the first spring 266 and moves toward the rod supporting portion 221 by supplying compressed air to the first pressure chamber 264. The fluid brake 260 includes a bottomed cylindrical first cylinder 262, and the first piston 261 is slidably accommodated in the first cylinder 262.

[0057] The first cylinder 262 is provided with a first port 63 for supplying and discharging compressed air. A first pressure chamber 264 communicating with the first port 63 is formed in the first cylinder 262. The first pressure chamber 264 is formed by the first piston 261 and the first cylinder 262. Compressed air is supplied or discharged to or from the first pressure chamber 264 in accordance with a predetermined brake operation.

[0058] <Spring brake 270>

[0059] The spring brake 270 is operated by compressed air as a fluid. The spring brake 270 has a second piston 271. The second pressure chamber 274 and the second spring 276 act on the second piston 271 in opposite directions. For the spring brake 270, by changing from a state in which compressed air as a fluid is supplied to the second pressure chamber 274 to a state in which compressed air as a fluid is discharged from the second pressure chamber 274, the second piston 271 moves in a direction close to the rod support 221 side, that is, in a braking direction (arrow Z1 direction) under the action of the force of the second spring 276. The spring brake 270 includes a second cylinder 272, and the second piston 271 is slidably accommodated in the second cylinder 272. The second cylinder 272 has approximately the same diameter as the first cylinder 262 and is connected via a partition 280.

[0060] A second spring 276 is disposed on the side opposite to the second pressure chamber 274 with respect to the second piston 271. The second spring 276 is compressed when receiving compressed air in the second pressure chamber 274. Normally, compressed air is introduced into the second pressure chamber 274, and the second spring 276 is compressed. However, by performing a predetermined braking operation such as parking, the compressed air in the second pressure chamber 274 is discharged, and the rod driving part 251 moves in the braking direction (arrow Z1 direction) under the action of the spring force of the second spring 276.

[0061] A through hole 281 is formed in the center of the partition wall portion 280. A shaft portion 282 is inserted into the through hole 281. The top end side of the shaft portion 282 is inserted into the through hole 281 in a movable manner. An external thread 284 is formed on the outer periphery of the base end side of the shaft portion 282. The external thread 284 of the shaft portion 282 is threadedly engaged with the cylindrical member 285. The second piston 271 moves integrally with the shaft portion 282. When the second piston 271 moves toward the rod support portion 221 side, the shaft portion 282 protrudes from the through hole 281 and abuts against the first piston 261, so that the second piston 271 and the first piston 261 move toward the rod support portion 221 side together. In addition, the shaft portion 282 functions as an output member.

[0062] The cylindrical member 285 having an internal thread formed on the inner circumferential surface is threadedly engaged with the external thread 284 of the shaft portion 282. A spring 287 is arranged between the cylindrical member 285 and the second piston 271. The cylindrical latch wheel 286 is slidably engaged with the outer circumference of the cylindrical member 285. The cylindrical member 285 is provided with a groove for guiding the latch wheel 286 in the axial direction. A flange portion 286A is provided at the base end of the latch wheel 286. A locking rod 291 for limiting the rotation of the flange portion 286A of the latch wheel 286 is arranged at the partition wall portion 280.

[0063] When the second piston 271 moves, the spring 287 and the shaft 282 threadedly engaged with the cylindrical member 285 pushed by the second piston 271 move together with the second piston 271. On the other hand, when the spring brake 270 is in effect, if the locking rod 291 is released, the latch wheel 286 can rotate. In addition, the first piston 261 is urged by the first spring 266 in a direction away from the rod support 221, so that the cylindrical member 285 and the latch wheel 286 rotate integrally, and the shaft 282 moves in the anti-braking direction (arrow Z2 direction). The rod driving part 251 moves in the anti-braking direction (arrow Z2 direction) together with the shaft 282, so that the rod 220 moves in the anti-braking direction (arrow Y2 direction).

[0064] <Brake release mechanism 290>

[0065] The brake release mechanism 290 includes the lock rod 291 as a restriction portion for restricting the rotation of the latch wheel 286 and as a release portion for manually releasing the restriction on the rotation of the latch wheel 286. The brake release mechanism 290 releases the restriction of the lock rod 291 by operating the lock rod 291 to allow the relative displacement between the shaft 282 and the second piston 271, thereby releasing the braking force of the spring brake 270. In addition, in the brake release mechanism 290, if the operation of the lock rod 291 is released, the rotation of the latch wheel 286 in the direction opposite to the reset direction is restricted. In addition, by supplying compressed air to the second pressure chamber 274 until the position of the second piston 271 relative to the shaft 282 is restored, the cylindrical member 285 and the latch wheel 286 are rotated in the reset direction, and the position of the shaft 282 relative to the second piston 271 is restored.

[0066] <Compressed air supply path>

[0067] like Figure 1 As shown, the brake cylinder device 250 includes: a first supply path 1, which is used to supply compressed air to the first pressure chamber 264; a second supply path 2, which supplies compressed air to the second pressure chamber 274 via the compound check valve 8; and a third supply path 3, which is connected between the first supply path 1 and the compound check valve 8.

[0068] The first supply passage 1 supplies compressed air from the first air source 4, and the supply and discharge of the compressed air to and from the first pressure chamber 264 are controlled by the fluid brake control device 5. The first supply passage 1 is connected to the first port 63. The fluid brake control device 5 changes the supply amount of compressed air according to the braking operation of the vehicle to change the braking amount.

[0069] The second supply path 2 supplies compressed air from a second air source 6 different from the first air source 4, and controls the supply of compressed air to the second pressure chamber 274 based on the control of the spring brake control solenoid valve 7. The second supply path 2 is connected to the second port 73. The spring brake control solenoid valve 7 supplies compressed air when the parking brake of the vehicle is not operated, thereby releasing the braking of the second spring 276. On the other hand, when the parking brake of the vehicle is operated, the spring brake control solenoid valve 7 discharges compressed air, thereby exerting a braking effect using the second spring 276.

[0070] The third supply passage 3 supplies compressed air to the second pressure chamber 274 via the double check valve 8 when supplying compressed air to the first pressure chamber 264, thereby supplying compressed air to the second pressure chamber 274 without taking the braking of the second spring 276 into account when supplying compressed air to the first pressure chamber 264. The double check valve 8 allows the compressed air of the higher pressure of the compressed air supplied from the spring brake control solenoid valve 7 of the second supply passage 2 and the compressed air supplied from the third supply passage 3 to flow to the second pressure chamber 274. In addition, as the fluid brake 260 operates, the third supply passage 3 functions as a counter-braking pressure imparting unit that imparts a counter-braking pressure to the second piston 271, and the counter-braking pressure is a pressure that causes the second piston 271 to move in the counter-braking direction (arrow Z2 direction) which is the opposite direction to the braking direction (arrow Z1 direction).

[0071] The third supply passage 3 is provided with a proportional pressure reducing valve 11, which serves as a restriction portion and a pressure control valve, and controls the pressure of the compressed air supplied to the second pressure chamber 274 so as to prevent the pressure from reaching a pressure at which the second piston 271 moves against the force of the second spring 276. The proportional pressure reducing valve 11 reduces the pressure of the compressed air supplied to the first supply passage 1 by a certain ratio and supplies the compressed air to the double check valve 8. In addition, the proportional pressure reducing valve 11 controls the counter-braking pressure applied to the second piston 271 to be smaller than the pressure at which the second piston 271 moves against the force of the second spring 276. The proportional pressure reducing valve 11 operates by utilizing the difference in the pressure receiving area of ​​the two rubber diaphragms, and therefore can be constructed to be lightweight and compact compared to the pressure limiting valve described later, and can also be installed on the chassis.

[0072] The brake cylinder device 250 includes a valve device 10 having a compound check valve 8 and a proportional pressure reducing valve 11. The valve device 10 supplies the compressed air supplied from the second air source 6 to the second pressure chamber 274 by using the compound check valve 8, and supplies the compressed air supplied from the first air source 4 to the second pressure chamber 274 via the compound check valve 8 after the pressure is controlled at the proportional pressure reducing valve 11 via the third supply path 3. The valve device 10 includes a connection port PA connected to the spring brake control solenoid valve 7 of the second supply path 2, a connection port PB connected to the second pressure chamber 274 of the second supply path 2, a connection port PC connected to the third supply path 3, and an exhaust port EX. Therefore, the valve device 10 can be easily replaced by installing it instead of the conventional compound check valve.

[0073] <Action>

[0074] Next, the operation of the unit brake 200 will be described.

[0075] First, the state in which the vehicle is not braked is described. In this state, the unit brake 200 is controlled by the fluid brake control device 5 so that the compressed air is not supplied from the first air source 4 to the first pressure chamber 264 via the first port 63. In addition, the compressed air in the first pressure chamber 264 is discharged from the fluid brake control device 5 via the first port 63. Therefore, the first spring 266 is used to apply force to the first piston 261 in the anti-braking direction (arrow Z2 direction), so that the first piston 261 is in contact with the partition wall 280.

[0076] On the other hand, the unit brake 200 supplies compressed air from the second air source 6 to the second pressure chamber 274 via the second port 73 based on the control of the spring brake control solenoid valve 7. Therefore, under the action of the compressed air supplied to the second pressure chamber 274, the second piston 271 overcomes the force of the second spring 276 and moves in the anti-braking direction (arrow Z2 direction).

[0077] Next, refer to Figure 2 The state in which the vehicle is braked by the spring brake 270 will be described.

[0078] like Figure 2 As shown, when the spring brake 270 is actuated, for example, when the fluid brake 260 is actuated to completely stop the railway vehicle, the spring brake 270 is actuated as a parking brake, etc. The spring brake 270 is actuated by discharging compressed air from the second pressure chamber 274 based on the control of the spring brake control solenoid valve 7.

[0079] When the compressed air supplied to the second pressure chamber 274 is discharged, the second piston 271 starts to move in the braking direction (arrow Z1 direction) under the action of the biasing force of the second spring 276. At this time, the shaft portion 282 pushed by the second piston 271 starts to move in the braking direction (arrow Z1 direction) together with the second piston 271. Then, if the second piston 271 starts to move together with the shaft portion 282 in this way, the shaft portion 282 abuts against the first piston 261 and moves in the braking direction (arrow Z1 direction) together with the first piston 261.

[0080] As the second piston 271 moves, the first piston 261 also moves in the braking direction (arrow Z1 direction) with the aid of the shaft 282. The cylindrical member 285 threadedly coupled to the shaft 282 moves together with the shaft 282 and is accommodated in the latch wheel 286. The rotation of the latch wheel 286 is restricted by the locking rod 291. Furthermore, since the rotation of the latch wheel 286 is restricted, when the second piston 271 moves in the braking direction (arrow Z1 direction) due to the force of the second spring 276, the first piston 261 and the shaft 282 remain in the state of moving in the braking direction (arrow Z1 direction). That is, the spring brake 270 is kept in the state of being actuated and the spring braking force acting.

[0081] Next, a case where the vehicle is braked by the spring brake 270 and the compressed air in the fluid brake 260 is also retained and becomes zero is described.

[0082] The lock lever 291 can be released manually, and when released, the latch wheel 286 can rotate, and the latch wheel 286 and the cylindrical member 285 rotate idly as a whole. In other words, the shaft 282 and the second piston 271 can be relatively displaced. The shaft 282 moves to the end of the stroke due to the force of the first spring 266, and the first piston 261 and the shaft 282 move in the anti-braking direction, and the braking force of the spring brake 270 is released.

[0083] As described above, according to this embodiment, the following effects can be obtained.

[0084] (1) After the braking force of the spring brake 270 is released by the brake release mechanism 290 for idling, if compressed air starts to be supplied to the first pressure chamber 264 in order to operate the fluid brake 260, the counter-brake pressure is applied to the second piston 271 by the third supply path 3 and the valve device 10 as the counter-brake pressure applying unit to move the second piston 271 in the counter-brake direction, but the counter-brake pressure is controlled by the proportional pressure reducing valve 11 as the pressure control valve to be smaller than the pressure that causes the second piston 271 to move against the biasing force of the second spring 276. Therefore, even if compressed air is supplied to utilize the fluid brake 260, it is possible to avoid a state in which the second piston 271 moves against the biasing force of the second spring 276 and compresses the second spring 276 to accumulate the braking force. Therefore, it is possible to appropriately avoid the release of the braking force of the spring brake 270 due to the compressed air supplied to the fluid brake 260 after the braking force of the spring brake 270 is released and reset.

[0085] (2) After the braking force of the spring brake 270 is released by the brake release mechanism 290 for idling, if the compressed air starts to be supplied from the first supply path 1 in order to activate the fluid brake 260, the same compressed air as the compressed air supplied to the first pressure chamber 264 is also supplied to the third supply path 3, but the pressure of the compressed air is controlled by the proportional pressure reducing valve 11 in the third supply path 3 so as not to reach a pressure that restores the position of the shaft portion 282 relative to the second piston 271, and then the compressed air is supplied to the compound check valve 8. Furthermore, if the compressed air is not supplied from the second supply path 2, the compressed air controlled by the proportional pressure reducing valve 11 of the third supply path 3 is supplied to the second pressure chamber 274 via the compound check valve 8, so that the release and restoration of the braking force of the spring brake 270 due to the pressure supplied from the third supply path 3 can be prevented.

[0086] (3) The proportional pressure reducing valve 11 can always reduce the pressure of the compressed air supplied from the first supply path 1 at a constant ratio.

[0087] (Second embodiment)

[0088] Below, refer to Figure 3 The second embodiment in which the brake cylinder device is implemented as a unit brake is described. In the first embodiment described above, the proportional pressure reducing valve 11 is used as the limiting part and the pressure control valve, but the brake cylinder device of this embodiment is as follows. Figure 3 As shown in the figure, a pressure limiting valve 12 is used instead. Hereinafter, the differences from the first embodiment will be mainly described.

[0089] The pressure limiting valve 12 limits the pressure of the compressed air supplied to the first supply path 1 to a predetermined pressure or less and then supplies the compressed air to the double check valve 8. The pressure limiting valve 12 can be formed with fewer parts than the proportional pressure reducing valve 11.

[0090] As described above, according to the present embodiment, in addition to the effects (1) and (2) of the first embodiment, the following effects can be obtained.

[0091] (4) The pressure of the compressed air supplied to the first supply passage 1 is limited to a predetermined pressure by the pressure limiting valve 12 and then supplied to the double check valve 8. Therefore, the compressed air can be reliably supplied to the second pressure chamber 274 when the fluid brake 260 starts to function.

[0092] (Third embodiment)

[0093] Below, refer to Figure 4 A brake system according to a third embodiment will be described. In this brake system, the valve device 10 described above is mounted on a chassis T. The valve device 10 of this brake system uses a proportional pressure reducing valve 11 as a pressure control valve.

[0094] <Brake System>

[0095] As Figure 4 shown, a vehicle body B (Body) is mounted on a chassis T (Truck) of a vehicle V (Vehicle). On each chassis T, there are provided: a plurality (two) of unit brakes 200 including a brake cylinder device 250 and a plurality (two) of brake chambers BC. Additionally, the chassis T may not include the brake chambers BC, and in this case, all the braking devices of the chassis T may be unit brakes 200. Here, the pipes provided between the chassis T and the vehicle body B are metal pipes, and basically no air leakage occurs. On the other hand, since the pipes between the chassis T and the vehicle body B move relative to each other, flexible air pipes H, HP are used for connection.

[0096] A source air storage pipe (Japanese: original air storage pipe) MRP (Main Reservoir Pipe) for supplying compressed air to the whole is passed through the vehicle body B. The source air storage pipe MRP is connected in series with a first air source 4 and a second air source 6. In the brake system, all the plurality of brake cylinder devices 250 of each chassis T are connected in parallel with a valve device 10. The valve device 10 is arranged on the chassis T, and the valve device 10 and the brake cylinder device 250 are connected in units of the chassis T.

[0097] A third supply path 3 is arranged on the chassis T. Compressed air is supplied from each third supply path 3 to each second pressure chamber 274 via the valve device 10. That is, compressed air is supplied from the first air source 4 and the second air source 6 on the vehicle body B side respectively, and the compressed air pressure-controlled by the valve device 10 provided on each chassis T is supplied to each brake cylinder device 250.

[0098] As described above, by adopting this embodiment, the following effects can be achieved.

[0099] (1) This brake system is a brake system in which a valve device 10 is provided on each chassis T respectively. Therefore, even if the air pipe HP of the second supply path 2 breaks by any chance, the parking brake of this chassis T still functions, but the compressed air of the fluid brake 260 of the first supply path 1 will not be discharged.

[0100] (Fourth Embodiment)

[0101] Hereinafter, Figure 5 the brake system of the fourth embodiment will be described. In this brake system, the above valve device 10 is mounted on the vehicle body B. The valve device 10 of this brake system uses a pressure limiting valve 12 as a pressure control valve.

[0102] <Brake System>

[0103] As Figure 5As shown, a vehicle body B is mounted on a chassis T (Truck) of a vehicle V (Vehicle). Each chassis T is provided with a plurality (two) of unit brakes 200 including a brake cylinder device 250 and a plurality (two) of brake chambers BC. In addition, the chassis T may not include a brake chamber BC, in which case the brake devices of the chassis T may all be unit brakes 200.

[0104] In the brake system, all brake cylinder devices 250 of one vehicle V are connected in parallel to the valve device 10. The valve device 10 is disposed on the vehicle body B, and the valve device 10 and the brake cylinder device 250 are connected in units of the vehicle V.

[0105] The third supply passage 3 is disposed in the vehicle body B. Compressed air is supplied from each third supply passage 3 to each second pressure chamber 274 via the valve device 10. That is, the pressure of the compressed air is limited by the valve device 10 on the vehicle body B side, and the compressed air whose pressure is limited in the chassis T and the compressed air on the high-pressure side of the compressed air from the second supply passage are supplied to the brake cylinder device 250.

[0106] As described above, according to this embodiment, the following effects can be obtained.

[0107] (1) Since the brake system is provided with the valve device 10 on the vehicle body B on the upstream side of each unit brake 200, the valve device 10 is reduced by half. In addition, when the air pipe HP is broken, the compressed air of the fluid brake 260 of the first supply path 1 is released from the broken air pipe HP to the atmosphere through the pressure limiting valve 12 through the double check valve 8. In order to delay the release of the compressed air, it is preferable to insert a throttle 15.

[0108] In addition, the above-mentioned embodiments can also be implemented in the following aspects obtained by appropriately changing the above-mentioned embodiments.

[0109] In the above-mentioned embodiment, the braking force of the spring brake 270 can be released either manually or mechanically.

[0110] In each of the above-mentioned embodiments, the nut member and the latch may be installed interchangeably.

[0111] In each of the above-mentioned embodiments, the compound check valve 8 may be built into the housing of the brake cylinder device 250. That is, the valve device 10 is separated into the compound check valve 8 and the pressure control valve (11, 12), the compound check valve 8 is built into the housing of the brake cylinder device 250, and the pressure control valve (11, 12) is provided outside the housing of the brake cylinder device 250, and the pressure control valve (11, 12) is connected to the compound check valve 8.

[0112] In the first and second embodiments, the brake cylinder device 250 is used in which the double check valve is not built into the housing. Fig. 9 As shown, in the case of a brake cylinder device 350 in which a compound check valve is built into a housing, a valve device 10 having a compound check valve 8 and a pressure control valve (11, 12) can also be provided. That is, the valve core 301 provided in the housing of the brake cylinder device 350 is fixed in a state of communicating with the second port 73 and the second pressure chamber 274, eliminating the function of the valve core 301 as a compound check valve, so that it can function in the same manner as the brake cylinder device 250.

[0113] In the third and fourth embodiments above, it is also possible to Figure 6 and Figure 7 As shown, a brake unit 300 having a brake cylinder device 350 is used, and the brake cylinder device 350 has a built-in double check valve. In this case, the valve core 301 provided in the housing of the brake cylinder device 350 is fixed as described above, so that it can function in the same way as the brake cylinder device 250 without a built-in double check valve in the housing.

[0114] In each of the above-described embodiments, the double check valve and the pressure control valve may be built into the housing of the brake cylinder device 250. That is, the valve device 10 may be built into the housing of the brake cylinder device 250.

[0115] In each of the above-mentioned embodiments, compressed air is used as the fluid, but oil may be used instead of the compressed air.

[0116] It is obvious to those skilled in the art that the present invention can be embodied in other unique ways without departing from the scope of its technical ideas. For example, a part of the components and features described in the embodiment (or one or more of them) may be omitted. The scope of the present invention should be determined with reference to the attached claims and the entire scope of equivalents granted by the claims.

Claims

1. A brake cylinder device, comprising: fluid a brake that generates braking force by supplying fluid; a spring brake which is independent of the fluid brake and generates a braking force by discharging the fluid; and a release portion for releasing the braking force of the spring brake, wherein the fluid is supplied to the spring brake in order to reduce the braking force of the spring brake when the fluid brake is in effect, wherein: The brake cylinder device comprises: a limiting portion for limiting the pressure of the fluid supplied to the spring brake to a predetermined pressure or less when the braking force of the spring brake is released by the release portion, the limiting portion being a pressure control valve that controls the pressure of the fluid to be lower than a pressure at which the spring brake whose braking force is released by the release portion is restored; and a compound check valve that supplies the fluid supplied to the fluid brake and the fluid supplied to the spring brake, whichever has a higher pressure, to the spring brake, The pressure control valve is located between the double check valve and a pressure source for supplying the fluid to the fluid brake.

2. The brake cylinder device according to claim 1, wherein: The pressure control valve is a proportional pressure reducing valve that reduces the pressure of the fluid at a certain ratio.

3. The brake cylinder device according to claim 1, wherein: The pressure control valve is a pressure limiting valve that limits the pressure of the fluid to be equal to or lower than the predetermined pressure.

4. A brake system provided in a railway vehicle having a vehicle body mounted on an underframe, wherein a plurality of brake cylinder devices according to any one of claims 1 to 3 are provided, the brake cylinder devices are connected in parallel and are connected in parallel with the pressure control valve, wherein: The pressure control valve is disposed on the vehicle body, and the pressure control valve and the brake cylinder device are connected in units of the vehicle body.

5. The braking system according to claim 4, wherein: A throttle is provided on the vehicle body side downstream of the pressure control valve.

6. A brake system provided in a railway vehicle having a vehicle body mounted on an underframe, wherein a plurality of brake cylinder devices according to any one of claims 1 to 3 are provided, the brake cylinder devices are connected in parallel and are connected in parallel with the pressure control valve, wherein: The pressure control valve is disposed on the base frame, and the pressure control valve and the brake cylinder device are connected in units of the base frame.

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