JPH07196032A - Brake control valve device for railroad rolling stock and its spool valve device - Google Patents

Abstract

PURPOSE: To provide a spool valve device which uses a booster spring to overcome the static friction of a spool valve O-ring to assure quick actuation of a spool valve member. CONSTITUTION: A booster spring 73 acts only during the movement of a spool valve member 39 from a loosening position to a braking position over a limited distance. The movement of the spool valve member 39 over the limited distance is selected to occur before the transition or switch of a port connection controlled by a spool valve 73. The necessity of increasing the spring of a spool valve return spring 41 in order to reset the spool valve member enough to reset the initial spool valve port connection is eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
Spools, such as those used in pneumatic control valves for rail freight vehicles, which have the primary function of communicating the air in the sump to the vehicle brake cylinders to provide an emergency brake pressure higher than the maximum achievable service brake pressure. The present invention relates to a valve device, particularly a high pressure spool valve.

[0002]

BACKGROUND OF THE INVENTION It is generally accepted that spool type valves are desirable in view of the ability to economically achieve substantially leak-free operation over a long service life. However, it is also recognized that the pressure seals that allow this can introduce a frictional component that provides resistance to spool valve actuation. Industrial standard ABD /
W type freight vehicle brake control valve and newer ABD
In the X-type valve, the high-pressure spool valve device has the main function of supplying a high pressure during emergency braking, and also provides the same suppression brake pressure when performing emergency braking in addition to normal braking as when performing direct emergency braking. To ensure, during emergency braking, the ability to capture the service brake pressure applied to the suppression valve piston and the time sufficient to prevent premature loosening of the emergency brake by ensuring a complete stop of the train, It is designed to provide an emergency room blowout function that delays recharging of vehicle brake pipe pressure after emergency braking.

In order to combine several such functions in a single spool valve, to prevent mutual leakage (lateral leakage) between several spool valve grooves that form a suitable pressure connection or communication, A number of O-ring seals are provided on the spool. As a result, high pressure spool valve systems operate the valve from the relaxed position and the emergency braking position due to the relatively strong friction between these O-ring seals and the spool bushes with which the O-ring seals sealingly engage. However, it may receive a considerably large starting resistance.

[0004]

For example, a high pressure spool valve may be actuated under pressure from a normal slack position to a braking position in response to emergency brake braking to achieve the above-described function and in that braking position. Is actuated by a return valve to reset or return the valve to its normal relaxed position.
Prior to such actuation to the braking or slack position, the spool valve would have the O-ring friction against valve actuation,
Therefore, it is in a static state where the frictional resistance is maximum. Therefore,
In order to overcome this static friction and reset the spool valve from the braking position to the loosening position, the force of the return spring must be relatively large. However, in such a case, the force exerted by the relatively strong return spring in the relaxed position is such that during emergency braking, the emergency braking operation of the high-pressure spool valve under very low pressure conditions is prevented. There arises a problem that the action force of the pressure is canceled out.

It is an object of the present invention to provide a spool valve system which utilizes a limited travel booster spring to overcome static start-up friction of the O-ring upon removal from the relaxed position. Especially. The use of the booster spring facilitates actuation of the spool valve in the emergency braking position without interfering with the action of the spool valve return spring acting in the opposite direction when the spool valve returns.

[0006]

To achieve the above object, according to the invention, a spool valve device for a brake control valve device for a rail vehicle receives fluid under pressure at both ends and around it. A spool member having at least one sealing ring surrounding it; and a bushing reciprocally arranged such that the spool member is axially movable between a relaxed position and a braking position. Having at least two axially spaced ports that are in communication with each other by a spool member at one of the relaxed position and the braking position and separated from each other by the spool member at the other position, and further in the direction of the relaxed position. The first spring acting on the spool member and the spool member from the loosening position to the braking position before switching between the communication state and the separation state of the two ports. Only while moving over a have limited distance and a second spring acting on the spool member in the direction of the braking position.

The above and other objects and advantages of the present invention will become apparent from the following detailed description of the invention with reference to the accompanying drawings.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, a common part 3 is shown.
(Only a portion is shown), and an emergency portion 5 and a standard known ABDW freight vehicle brake control valve 1 having a pipe bracket 7 to which the service and emergency portions are bolted. Connected to the pipe bracket 7 via pipes 9, 11, 13, 15 and 17 is the auxiliary air reservoir 1
9, an exhaust stop valve 21, an emergency air reservoir 23, a brake cylinder 25, and a vehicle brake pipe 27.

The emergency part 5 includes an emergency valve 29 and a relief valve 3.
1, a suppression valve 33 and a high pressure valve 35 are included. All of these valves are shown in the positions they take in response to the filling of the brake pipe 27. Further, due to this charging, the auxiliary air reservoir 19, the emergency air reservoir 23, and the rapid chamber 37 formed in the pipe bracket 7 are also filled to the operating pressure held in the brake pipe.

In the high pressure valve 35, the spool valve member 39 is biased by the return spring 41 toward the loosened position, as shown in the figure. Also, the brake pipe pressure is
Is supplied to the chamber 42 on the upper side of the spool valve member 39 via, and strengthens the return spring 41. In this loosened position, the spool valve member 39 has the emergency air reservoir 23 and the pipe 1
3, the passage 13a from 3 is closed, and the passage 15a from the brake cylinder 25 and the pipe 15 to the suppression valve control chamber 45.
And the passage 47 from the emergency valve 29 is connected to the escape passage 49 via the first passage 49a. Emergency valve 29
The other passage 51 from the chamber 53 below the spool valve 39.
To the escape passage 49 via the second throttle channel 49b. A total of five O-rings 55, 57, 59, 61 and 63 are installed around the spool valve member 39 to prevent mutual leakage between the blocked passages of these passages. And forms a pressure seal with the body on which the spool valve member 39 operates. In a practical example, this body is a bush 65 as shown in FIGS. 2 to 4, but is omitted in the simplified view of FIG. 1 for the sake of clarity.

Referring to FIGS. 2-4, the spool valve member 39 is operably disposed within the bore 67 of the bush 59 and comprises a plurality of spaced apart annular O-ring seals 5.
In addition to 5 to 63, it has a first annular groove 69 between the O-ring seals 57 and 59 and another annular groove 71 between the O-ring seals 61 and 63. Passages 13a, 15a, 4
5, 47 and 49 are connected to hole 67 by a series of radial connection ports 13b, 15b, 45b, 47b and 49a ', 49b' provided on bush 65, respectively. Here, the connection ports 49a 'and 49b' correspond to the above-described first and second flow paths 49a and 49b shown in FIG.

During braking by the service brake, the decrease in the brake pipe pressure reflects the decrease in the pressure in the chamber 42 of the high pressure valve 35 and the pressure in the emergency valve 29. But,
As the jerk chamber pressure fluctuates in a known manner, the reduction of the brake pipe pressure is offset by the emergency valve 29, so that the emergency valve 2
9 is stabilized in the relaxed position shown. Chamber 5 of high pressure valve 35
The passage 51 leading to 3 is cut off from the sudden chamber pressure at the loosened position of the emergency valve 29 to prevent the operation of the high pressure spool valve member 39.

When the emergency brake is applied, the brake pipe pressure decreases at a faster rate than when the service brake is applied, and as a result, fluctuations in the sudden chamber pressure compensate for the decrease in brake pipe pressure during emergency braking. It becomes impossible to do. Therefore, a pressure differential is created across the emergency valve 29, which
The emergency valve 29 is operated to the emergency position. As is known, in the emergency position, the jerk chamber pressure is connected to the relief valve control chamber (FIG. 1) and the passage 51 leading to the chamber 53 under the control of the high pressure spool valve member 39. By connecting the sudden chamber pressure to the escape passage 49 via the radial connection port 49a ′ including the throttle passage 49b in the high pressure valve 35, the rapid chamber pressure rises in the passage 51. As a result, the relief valve 31 is actuated, the brake pipe pressure is drained very rapidly, and emergency braking is performed. The downward brake pipe pressure load in the upper chamber 42 of the high pressure spool valve member 39 is removed. At the same time, the pressure in passage 51 rises in chamber 53 sufficiently to overcome the resistance of the O-ring to spool valve member 39 and return spring 41, thereby causing spool valve member 39 to move upward into the braking position. Is transitioned to. This actuation of the high pressure spool valve 35 preferably occurs at the lowest possible pressure.

At various positions of the spool valve member 39 between the loosening position and the braking position, the transition of the communication relationship by the spool valve member described above occurs.

In the braking position, the spool valve member 39
Is an auxiliary air reservoir pressure that is provided by a service valve (not shown) provided in the service part 3 that connects the emergency air storage pressure of the path 13a to the passage 15a reaching the brake cylinder 25 via the suppression valve 33. Together, they enable the desired high brake cylinder pressure in emergency braking and allow passage 4
5 is closed to capture the auxiliary air reservoir pressure existing in the suppression valve control chamber from the preceding service brake braking, and thus the same as that obtained when performing direct emergency braking during emergency braking in addition to service braking. The pressure of the suppression valve is ensured, and the passage 47 is escaped to the passage 4
Separating from 9 to stop the fluctuation of the pressure in the rush chamber, and
1 and the sudden chamber pressure in the chamber 53 below the spool valve member 39 is connected to the escape passage 49 via radial ports 49a ′ and 49b ′ including parallel flow passages 49a and 49b,
As a result, the sudden chamber pressure is started to be blown out through the blowing throttle valve 55 (see FIG. 1) that suppresses the discharge of the relief valve control pressure, and the closing of the relief valve 31 is delayed by about 60 seconds. The relief valve remains open until this delay period elapses, preventing the brake pipe 27 from recharging and the brake from loosening.

Note that the spring force of the return spring 41 resets the spool valve 39 to its original loosening position following the blowout of the sudden chamber pressure from the chamber 53 below the spool valve member 39. This return of the spool valve member 39 to its original relaxed position should occur before brake pipe pressure is supplied to the chamber 42 above the spool valve member 39 during brake release and refill. For this reason, the return spring 41
Is a relatively high O that resists movement of the spool valve member 39.
It must be strong enough to overcome ring friction. Therefore, as is apparent, if the return spring 41 is made strong enough to ensure the return of the spool valve member 39 from the braking position to the loosening position, this relatively strong spring force causes the spool valve member 39 to move in the opposite direction, , The action against the movement in the direction from the loosening position to the braking position occurs.

According to one embodiment of the present invention, in order to ensure a quick actuation of the spool valve member 39 in response to emergency braking, especially when the static friction of the spool valve O-ring is strong,
As shown in FIGS. 2 to 4, a spiral coil type booster spring 73 is provided. The strong static friction of the spool valve O-ring as described above, in combination with the force of the return spring 41, may cause a resistance to actuation of the spool valve member 39 that is higher than desired. Therefore, the booster spring 73 is compressed at the loosening position by the force of the brake pipe pressure acting downward on the spool. The booster spring 73 allows the spool valve member 3 to move only by moving the spool valve member a limited distance.
9 abuts on the lower side. In order to accommodate this booster spring 73, the outer diameter of the existing standard high pressure spool valve member 39 is
It decreases in the area between the O-ring 63 and the lower end of the spool valve member 39. The free height of the booster spring 73 is such that an upward force is applied to the spool valve member 39 at a limited movement distance of the spool valve member 39, thereby causing a sudden movement in the chamber 53 acting on the lower side of the spool valve member 39. The force of the chamber pressure is reinforced, thus overcoming the above resistance to actuation of the spool valve member due to the force due to the static friction of the return spring 41 and the spool valve O-ring during emergency braking, and thus the high pressure valve 35 quickly. Has realized a reliable valve opening response. As shown in FIG. 2, the spool valve member 39 is maintained in the loosened position by the combined force of the brake pipe pressure in the chamber 42 and the force of the return spring 41 following the filling of the brake control valve 1.
In this loosened position, the booster spring 73 is in a compressed state, in which case the amount of compression from the free height of the booster spring is relatively small, so that this booster spring 73 is compressed from the loosened position in which it is compressed. It only acts over a relatively short distance of travel of the spool valve member 39 towards an unbraked braking position. The maximum force exerted by the booster spring 73 on the spool valve member 39 is greater than the opposite force exerted by the return spring 41 until the booster spring 73 is almost fully extended.

As already mentioned, when emergency braking is applied, the sudden chamber pressure is connected by the emergency valve 29 to the chamber 53 below the high-pressure spool valve member 39 and at the same time the chamber 42 above the spool valve member 39. The brake pipe pressure inside is discharged. The reduction of the brake pipe pressure in the chamber 42 causes the return spring 41
By itself, it is not sufficient to maintain the spool valve member 39 in its relaxed position. As a result, the spool valve member 3 is subjected to the combined force of the force of the booster spring 73 and the pressure in the chamber 53 due to the movement of the spool valve member over a limited distance.
9, an initial motion occurs, and this initial motion is performed until the booster spring 73 extends to the full length or the free height.
During this limited movement of the spool valve member 39, there is no transition in communication or communication with the port of the spool valve member, and thus the booster spring 73 tends to delay the initial operation of the spool valve member 39. It only acts to facilitate overcoming the static friction of the ring.

The position of the spool valve member 39 at the free height of the booster spring 73 is shown in FIG. In this position, the O-ring 63 does not cross the port 49a 'of the bush, and this transition is an initial control function of the spool valve member 39 associated with emergency braking. Spool valve member 39
The ascending distance to move from the loose position to this initial transition position is 0.105 to 0.135 inches (2.667 to 3.429 m).
m), which corresponds to the maximum amount of deformation from the compressed state to the free height at the loosened position of the booster spring 73.
In this position of the spool valve member 39, the spool valve member 39 must be moved further upwards in order to realize another port communication transition by the high pressure valve 35. What is important here is that the force of the booster spring 73 acts on the spool valve member 39 only before the initial port communication transition that occurs during the movement of the spool valve from the loosening position to the braking position, and thereafter the acting force of the booster spring 73. Is a point that does not exist. Apart from this limited action of the booster spring 73,
The high pressure valve of the present invention operates in the same manner as existing standard high pressure valves, thus making the same port connections in the same sequence without having to change the placement of spool valve O-rings and / or each connection port of bush 65. be able to.

In the state shown in FIG. 3, the port connection made by the spool valve member 39 in the emergency braking position has been achieved as already explained and the chamber 53 acting below the spool valve member 39. After the internal pressure of the sudden motion chamber is blown out, the return spring 41 is brought into the operating state to move the spool valve member 39 downward toward the loosening position. The spool valve member 39 does not re-engage with the booster spring 73 until it has moved beyond the initial transition position, so all original port connections are reset without any impact from the booster spring 73. Will be done.
In this connection, the force of the return spring 41 causes the booster spring 7
It does not need to be increased to account for the additional reaction force of 3.
This is because the booster spring effectively does not work until all port transitions have been made. In this way, when the original port connection is re-established, the brake pipe pressure is connected to the chamber 42 above the spool valve member 39 during the relief of the emergency braking, whereby the spool valve member 39 is directed downwards. The pressure difference acting on is added. This downwardly acting pressure difference, in combination with the spring force of the return spring 41, drives the spool valve member 39 to the fully loosened position against the opposite force of the booster spring 73. in this case,
The booster spring 73 is compressed from the free height, exerts an auxiliary acting force on the spool valve member 39, and becomes a state in which it can act during the next emergency braking. In this way, the energy stored in the booster spring 73 in the compressed state that applies the above-mentioned auxiliary action force to the spool valve member 39 is returned to the return spring 41.
Resulting from the brake pipe pressure acting on the spool valve member 39 after the spool valve has been moved to the intermediate position.

Next, in another embodiment of the present invention shown in FIG. 5, a disc-shaped booster spring 75 generally known as a disc spring is used. The booster spring 75 is arranged in the chamber 53 formed in the spool hole 67 so as to act between the bottom of the spool hole and the lower side of the spool valve member 39.

FIG. 6 shows another embodiment of the present invention in which the booster spring is a wave spring 7.
7 This spring 77 is also arranged in the chamber 53 formed between the bottom of the spool hole 67 and the spool valve member 39.

Similar to the case of using the booster spring 73 which is a coil spring, the above-mentioned springs 75 and 77 are held in the compressed state in the normal loosened position corresponding to the position shown in FIG. Accordingly, the spool valve member 39 is acted upon by sufficient force to overcome the static friction of the spool valve O-ring seal, thereby causing the sudden chamber pressure supplied to the chamber 53 when emergency braking is required. A fast and reliable actuation of the supporting spool valve member 39 is ensured. These springs 75 and 77 extend to the free height or relaxed state just before reaching the intermediate position shown in FIGS. 5 and 6 where the initial transition of the spool valve connection occurs.

Unlike the configuration using the booster spring 73, the assembly of the above springs 75 and 77 does not require modification or modification of the spool valve member 39 or the body accommodating the spool valve member.

[0025]

As is apparent from the above description, the booster springs 73, 75 and 77 provide a positive assisting force acting on the spool valve member 39 of the high pressure valve 35, and thereby,
In response to emergency braking, rapid and reliable valve actuation is possible despite prolonged non-use or excessive O-ring friction that delays or prevents valve actuation. , Is ensured without any adverse effect on the functional requirements of the high pressure valve.

[Brief description of drawings]

FIG. 1 is a simplified view of a conventionally known brake control valve device for a freight vehicle, showing a high pressure valve device to which the present invention relates.

2 is a partial cross-sectional assembly view of the high pressure valve device of FIG. 1 with the spool valve member in a loosened position, wherein the high pressure valve device is provided with a coil spring type booster spring shown in a compressed state. .

FIG. 3 is a partial cross-sectional assembly view showing the high pressure spool valve of the present invention in the braking position away from the booster spring.

FIG. 4 is a partial cross-sectional assembly view of the high pressure spool valve of the present invention in an intermediate position in which the booster spring is extended to a free height just prior to its removal from the spool valve member.

FIG. 5 is a partial cross-sectional assembly view showing another embodiment of the present invention in which the booster spring is in the form of a disc spring such as a disc spring.

FIG. 6 is a partial cross-sectional assembly view showing yet another embodiment of the present invention in which the booster spring is in the form of a wave spring.

[Description of Reference Signs] 1 ... Brake control valve, 13b, 15b, 45b, 47
b, 49a ', 49b' ... ports, 13a, 15a, 4
5, 47, 49, 51 ... Passage, 23 ... Emergency air reservoir, 2
5 ... Brake cylinder, 27 ... Brake pipe, 33 ... Suppression valve, 35 ... High pressure valve, 37 ... Rapid chamber, 39 ... Spool member (spool valve member), 41 ... First spring (return spring),
55, 57, 59, 61, 63 ... Pressure seal (O-ring), 65 ... Bush, 67 ... Hole, 73, 75, 77 ...
Second spring (booster spring).

Front Page Continuation (72) Inventor John Bee Carroll Janet Circle, Irwin, Pennsylvania, USA 22

Claims (15)

[Claims] 1. A spool valve arrangement for a rail vehicle brake control valve arrangement comprising: a) at least one annular pressure seal, the two ends of which receive fluid under pressure and which surrounds the periphery. A pressure-actuated spool member having: b) a hole in which the spool member is reciprocally arranged so as to be axially movable in both directions between a first position and a second position; While opening in the hole, the spool member communicates with each other at one of the first position and the second position, and the spool member at the other position of the first position and the second position by the spool member. At least two axially spaced ports that are separated from each other to provide a brake control function; and d) the spool member is in a position intermediate the first and second positions. A transition between said at least two ports in said communicating and said separated states, and e) a first acting on said spool member in the direction of said first position. A spring; and f) a second acting on the spool member in a direction opposite to the first spring without extending to a limited distance from the first position of the spool member and to the intermediate position. And a spool valve device of a brake control valve device for a railway vehicle, comprising: 2. The second spring is compressed in a relaxed position, which is the first position, and the spool member is moved during movement of the spool member from the relaxed position to the braking position, which is the second position. The spool valve device according to claim 1, wherein the spool valve device is extended to a free height before the intermediate position is reached. 3. The second spring is substantially 2.66 from its free height in the relaxed position of the spool member.
The spool valve device according to claim 2, wherein the spool valve device is compressed by 7 to 3.429 mm. 4. The second spring is positioned within the hole to engage one end of the hole and the spool member during movement of the spool member the limited distance. The spool valve device according to claim 3, wherein the second spring is detachable from one of the spool member and one end of the hole after the spool member moves the limited distance. 5. The spool valve device according to claim 2, wherein the second spring is a coil spring. 6. The spool valve device according to claim 2, wherein the second spring is a disc-shaped disc spring. 7. The spool valve device according to claim 2, wherein the second spring is a wave spring. 8. A brake control valve device for a railway vehicle having a brake pipe, a brake cylinder, and an emergency air reservoir filled with pressure in the brake pipe, wherein: a) the pressure retained in the brake pipe. B) a high pressure valve means for performing an emergency brake control function; and c) for responding to an emergency reduction rate of fluid in the brake pipe under pilot pressure of the high pressure valve means. D) the high-pressure valve means includes one end that receives fluid under pressure in the brake pipe and the other end that receives fluid under pressure in the rush chamber. The spool member has a first pressure seal surrounding the periphery thereof, and (ii) a bush in which the spool member is reciprocably arranged so as to be axially movable between a loosening position and a braking position. And wherein the bush comprises first and second ports to which the emergency air reservoir and the brake cylinder are respectively connected, the first pressure seal being the first pressure seal in the loosened position of the spool member. Located between the first and second ports to block fluid pressure communication between the first and second ports, and to displace from the intermediate position to the braking position of the spool member. A fluid pressure communication state is secured between the two ports, thereby enabling the first aspect of the emergency brake control function, and (iii) the first spring acting on the spool member in the direction of the loosened position. (Iv) while the spool member moves from the loosened position to the braking position before the first pressure seal is displaced from the position between the first and second ports, and 1
A second spring acting on the spool member in the direction of the braking position only while the spool member moves from the braking position to the loosening position after alignment of the pressure seal between the first and second ports. It has a brake control valve device for railway vehicles. 9. The brake control valve device for a railway vehicle according to claim 8, comprising: a) suppression valve means for connecting the fluid in the emergency air reservoir under pressure to the brake cylinder; and b) the bush. Further comprises a third port to which said suppression valve means is connected, and c) said spool member comprises a second pressure seal surrounding its periphery, said second pressure seal comprising said spool member said It is located between the second port and the third port in the braking position to cut off fluid pressure communication between the second port and the third port, and is in the loosening position to communicate with the second port. Displacement from the position between the third port and the third port ensures fluid communication between the second port and the third port, thus enabling the second aspect of the emergency brake control function. Cage, d) the first Of the spring during movement of the spool member from the relaxed position to the braking position before the second pressure seal is aligned between the second and third ports, and the second pressure seal A brake control valve device for a rail vehicle, which acts on the spool member only while the spool member is moving from the braking position to the loosening position after being displaced from the aligned position between the second and third ports. 10. The spool member further comprises the second
Adjacent to and surrounding the pressure seal of the third pressure seal, the third pressure seal on the side of the spool member opposite the second pressure seal in the braking position of the third pressure seal. The brake control valve device for a railway vehicle according to claim 9, which is located at a port. 11. The railway vehicle brake control valve device according to claim 10, wherein: a) the bush further comprises a fourth port communicating with the atmosphere; and b) the spool member further comprises: A fourth pressure seal is provided surrounding the periphery of the fourth pressure seal, the fourth pressure seal being adjacent to the opposite side of the spool member and being one side of the fourth port when the spool member is in the loosened position. Fluid pressure communication through the fourth port is cut off, and when the spool valve is in the braking position, the fluid pressure through the fourth port is located on the other side of the fourth port. Establishing communication, thereby enabling the third aspect of the emergency brake control function, c) the second spring having the fourth pressure seal disposed on the other side of the fourth port. Before the spool member is in the loose position. Only from the stationary position to the braking position, and only while the spool member moves from the braking position to the loosening position after the fourth pressure seal is disposed on the one side of the fourth port, The brake control valve device for a railway vehicle according to claim 10, which acts on the spool member. 12. The second spring is substantially 2. from its free height in the relaxed position of the spool member.
667-3.429 mm compressed so that any one of the first, second and fourth pressure seals has the first,
Before crossing any of the second, third and fourth ports,
The brake control valve device for a railway vehicle according to claim 11, wherein a distance that the spool member moves from the loosened position toward the braking position is at least 3.048 mm. 13. The railway vehicle brake control valve device according to claim 8, wherein the second spring is a coil spring. 14. The brake control valve device for a railway vehicle according to claim 8, wherein the second spring is a disc-shaped disc spring. 15. The railway vehicle brake control valve device according to claim 8, wherein the second spring is a wave spring.