JPH01115762A - Multistage relay valve for railway vehicle - Google Patents

Abstract

PURPOSE:To enable proportional increase and decrease of a pressure, by a method wherein, in a multistage relay valve to output pressure air according to a brake command formed by a digital signal, an effective area in which output air is exerted as a balance force on a balance piston is switchable to first and second areas. CONSTITUTION:A multistage relay valve DRV outputs air with a pressure generated according to a brake command formed by digital signals from normally demagnetizing type first solenoid valves MV1-MV3 and a normally exiting second solenoid valve EBV. The multistage relay valve is partitioned into a feed chamber D connected to a pressure air source MR, an output chamber F connected to a brake cylinder BC, an exhaust chamber E, a balance chamber C5 communicated to the output chamber F, first control chambers C1-C3, and a second control chamber C4. In this case, a balance piston S5 is additionally situated between a partition wall Q and a balance and control piston S4, and balance chambers C5 and C6 are formed on both sides of the piston balance. The balance chamber C6 is communicated to an output chamber F, and the balance chamber C5 is connected to the output chamber F through a third solenoid valve MV5.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is used in a digital electric command type air brake system for railway vehicles, and is a multi-stage brake system that outputs air at a pressure according to a brake command consisting of a digital electric signal. Regarding relay valves.

[Conventional technology]

As a conventional example of this type of multi-stage relay valve, the present applicant
"NABCO Technical Report" published on January 1, 1987
, pages 46 to 49 (particularly FIGS. 3 and 4), which is shown in FIG. 7 and described below.

In Figure 7, ite, MVI, MV2. MV3 is the first solenoid valve that is always demagnetized, EBV is the second solenoid valve that is always energized, and DRV is the solenoid valve MVI to MV3, the pressure corresponding to the brake command consisting of the excitation and demagnetization of EBV, that is, a digital electric signal. This is a multi-stage relay valve that outputs air.

First solenoid valve MVI, MV2. MV3 has the same configuration, and corresponds to the air supply port a connected to the output side of the variable load valve VLV via the first throttle NVI, and the first control chambers C1, C2, and C3 of the multistage relay valve DRV, respectively. The supply/exhaust port that is connected to the air supply/exhaust port has an exhaust port Ex that is open to the atmosphere. When it is in communication with Ex and is energized, it blocks the supply/discharge port A from the exhaust port Ex and communicates the air supply port a with the supply/discharge port A.

The second solenoid valve EBV is connected to an air supply port a connected to the output side of the variable load valve VLV through a second throttle NV2 having a larger diameter than the first throttle NVI, and to a second control chamber C4 of the multistage relay valve DR■. The connecting supply/discharge port has an exhaust port Ex open to the atmosphere, and in the illustrated excited state, the supply/discharge port A is connected to the supply/discharge port Ex.
When the air supply/discharge port A is cut off from the exhaust port Ex and the air supply/discharge port A is communicated with the exhaust port Ex, and demagnetized, the supply/discharge port A is cut off from the exhaust port Ex and the air supply/discharge port A is communicated with the air supply/discharge port Ex.

The multi-stage relay valve DRV includes an air supply chamber connected to the pressure air source MR, an output chamber F connected to the brake cylinder BC, an exhaust chamber E open to the atmosphere, and a fishing rod connected to the output chamber F. It is divided into a joint room C5, and the second control room C4 and first control rooms 01 to C3.

An air supply hole H is formed in the center of the first partition wall G that partitions the air supply chamber and the output chamber F, and communicates the air supply chamber and the output chamber F;
A valve seat I is provided protruding around the air supply chamber side of this air supply hole H, and an air supply valve K biased by a weak return spring J in the direction of seating on this valve seat I is provided in the air supply chamber. It is being

A hollow non-air valve rod M is inserted into the second partition wall that partitions the output chamber F and the exhaust chamber E so as to be slidable in an airtight manner, and its tip loosely fits into the air supply hole H and connects to the air supply valve K. They face each other, and one side opens at the tip and the other side opens into the exhaust chamber E.

A second connecting rod N is fixed to the center of the balancing and second control piston S4 that partitions the balancing chamber C5 and the second control chamber C4. It passes through the third partition Q that partitions the joint chamber C5 in an airtight and slidable manner, and its tip is connected to the exhaust valve rod M. Note that a weak return spring R is provided between the piston S4 and the third partition Q, and has a biasing force in a direction (downward in the figure) that moves the exhaust valve rod M away from the intake valve K.

First control pistons SL, S2. The S3 are connected to each other by a first connecting rod T, and the tip of the first connecting rod T can freely come into contact with and separate from the second connecting rod N in the second control chamber C4.

Table 1 outlines the operation of the multi-stage relay valve DRV having the above configuration. In Table 1, the notches indicate the stages of the brake command, and each solenoid valve MVI to MV3. EBV “1”
"0" means excitation, and "0" means demagnetization, which corresponds to the brake command. In addition, the effective area ratio of the pistons Sl to S4 is S4:Sl:S2:53=9:'l:6:4
Shows the output air pressure stages when set to .

Figure 7 of Table 1 shows the condition of relaxation in Table 1.
The solenoid valves MVI to MV3 are demagnetized and the second solenoid valve EBV
Since these solenoid valves are energized, all of these solenoid valves communicate their supply/discharge ports with the exhaust port Ex.

Therefore, the multi-stage relay valve DRV has control rooms 01-C.
4 is exhausted, the exhaust valve rod M moves downward in the figure due to the biasing force of the return spring R, and its tip reaches the air supply valve K.
The brake cylinder BC is evacuated to atmospheric pressure. At this time, the air supply valve is seated on the valve seat (■).

In the brake condition shown in FIG. 7 above, when a brake command of 10,000 is issued from the brake controller (not shown), the first solenoid valve MVI is energized, and the output air of the variable load valve VLV is
The first control room C1 of the multi-stage relay valve DRV via the solenoid valve MV1
is supplied with air.

The air supplied to the first control chamber ci pushes the first control piston S1 upward in the figure, and also pushes the first control piston S1 upward in the figure.
2 in the downward direction in the figure, and its piston Sl; Since the area ratio of S2 is 7:6, if the output air pressure of the variable load valve VLV is Pl, the exhaust valve rod M is directed toward the intake valve (in the figure). The command force to push upwards inside is PIX (7-6) = IXP
It is 1.

This command force causes the exhaust valve stem M to move upward in the figure, so that its tip comes into contact with the air supply valve K, and further causes the air supply valve K to leave the valve seat I. Therefore, the air supply chamber communicates with the output chamber F and supplies air to the brake cylinder BC. This is called air supply operation.

Accompanying this air supply operation, the output air pressure fed back to the balancing chamber C5 increases, and the balancing force opposing the command force increases. When the balancing force becomes approximately equal to the command force, the air supply valve K, with the tip of the exhaust valve stem M remaining in contact with it, is seated on the valve seat (2), and the output air pressure at that time is maintained. This is called an overlapping state. At this time, if the output air pressure is P2, the balancing force is P2×9, and 9×P2=
1×P1, the output air pressure P2 is P2=(1/
9) xPl. This (1/9) is shown in the output pressure stage of Table 1 above.

Furthermore, when an emergency brake command is issued in the wet condition shown in FIG. 7, all the solenoid valves are demagnetized and air is supplied only to the second control chamber C4 of the multi-stage relay valve DRV from the second solenoid valve EBV.

The pressurized air in this second control chamber C4 is supplied to the first control piston S1.
is pushed downward in the figure, and the counterbalance/second control piston S4
In order to push upward in the figure, the command force is 9×P1.

Air supply is activated by this command force, and then an overlapping state occurs. In this overlapping state, the balancing force is P2×9, and 9xP2=9xP1, so the output air pressure P2
is P2=(9/9)XPI, and this (9/9) is shown in the output pressure stage of Table 1 above.

In the above-mentioned shaped state, when an unloading command is issued, the multi-stage relay valve DRV performs an exhaust operation and returns to the unloaded state shown in FIG. 7.

The brake operations for the 2nd to 8th notches in Table 1 above are the same as those described above, so the explanation thereof will be omitted. Also,
Depending on the brake device, the 8 notches in Table 1 may be deleted.

[Problem that the invention seeks to solve]

Recently, with plans to increase the speed of trains on conventional lines, there has been a demand for increasing the output air pressure of the air brake device equipped with the above-mentioned multi-stage relay valve. Furthermore, depending on the friction characteristics of the brake shoes, it is also possible to reduce the output air pressure.

Therefore, a possible solution to these demands is shown in FIG. 8. However, FIG. 8 is not publicly known.

In FIG. 8, 320 is a control piston attached to the bottom wall U side, and this control piston 520 is connected to the two control chambers C.
21 and C22.

Then, the pressure is increased by opening one control room C21 to the atmosphere and introducing the output air of the variable load valve VLV into the other control room C22, and also opening the other control room C22 to the atmosphere and The variable load valve V is installed in one control room C21.
The pressure is reduced by introducing L and V output air.

However, when using the above means, there are the following problems.

First, when increasing the pressure, if the effective area ratio of the control piston S20 is 1, the output pressure in Table 1 above is
, 1 notch (2/9), 2 notches (3/9), 3 notches (4/9), 4 notches (5/9), 5 notches (6/9)
, 6 notches (7/9), 7 notches (8/9), 8 notches (9/9).

Emergency (9/9).

In other words, in this case, although pressure can be increased when the service brake is commanded from 1 to 7 notches, the problem is that the pressure increase is a constant amount (1/9) at every notch, and a proportional pressure increase cannot be obtained. be.

In addition, when attempting to reduce the pressure, the control piston S2
If the effective area ratio of 0 is 1, the output pressure in Table 1 above is:
Yuru i (0), 1notsuchi (0).

2 notches (1/9), 3 notches (2/9), 4 notches (
3/9), 5 notch (4/9), 6 notch (5/9),
7 notches (6/9), 8 notches (9/9), emergency (9/9)
9).

That is, in this case, although pressure can be reduced when a service brake command is issued for 1 to 7 notches, the pressure reduction is a constant amount (1/9) at any notch, and there is a problem that a proportional pressure reduction cannot be obtained.

[Means for solving problems]

Therefore, the means of the present invention for solving the above problem is as follows.
In the conventional multi-stage relay valve as shown in the figure, the effective area on which the output air acts as a balancing force on the balancing piston is configured to be switched between a normal first area and a second area that is larger or smaller than the normal first area. That's true.

[action, effect]

According to the above means of the present invention, the first area of the balancing piston is At, the second area is A2, the effective area where air pressure acts on the control piston as a command force is B, and the command air pressure acting on the control piston is Pl, the output air pressure when the first area A1 is P21, and the output air pressure when the second area A2 is P22, then when switching to the normal first area A1, P21xA1-PlxB holds, so the output Air pressure P21 = (B/AI)XPI, and when switching to the second area A2, P22xA2 = P1xB holds, so the output air pressure P
22=(B/A2)XPI.

Here, if AI>A2 is set, then P21<P2
2, and by switching to the smaller second area A2,
The output air pressure P22 can be increased from the normal pressure P21 for any brake command, and since the effective area B changes according to the brake command, the pressure increase is a proportional pressure increase.

Also, if you set AI<A2, P21>P22,
By switching to the larger second area A2, the output air pressure P22 can be reduced from the normal P21 for any brake command, and since the effective area B changes according to the brake command, The pressure reduction will be a proportional reduction.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 6. Regarding the same components as the conventional example, please refer to Section 7.
The same reference numerals as those in the drawings are used to omit the explanation.

Fig. 1 shows the first embodiment (pressure increase type), and the difference from the conventional example shown in Fig. 7 is that a balance piston S5 is added between the third partition Q and the balance/second control piston S4. The balance chamber C6 of this example is always communicated with the output chamber F, and the balance chamber C5 on the other side is connected to the output chamber F via the third electromagnetic valve MV5. Note that the piston S4. The area ratio of S5 is set as S4:55=9:6, and the area ratio of the first control pistons 81 to S3 is the same as the conventional example, which is Sl:S2:S3F:6:4. .

The third solenoid valve MV5 normally switches the pressure increase, and has an air supply port a connected to the output chamber F via the third throttle NV3, and an air supply/discharge port communicating with the balance chamber C5. , has an exhaust port Ex open to the atmosphere, and is of a constant demagnetization type,
At the time of demagnetization shown in FIG. 1, the supply/discharge port A is cut off from the exhaust port Ex, and the air supply port A is communicated with the supply/discharge port A, and when it is energized, the state is switched from the state shown in FIG. The supply/discharge port A is shut off from the air supply port a, and the supply/discharge port A is communicated with the exhaust port Ex.

That is, when the third solenoid valve MV5 is demagnetized, the
Since the two balancing chambers C5 and C6 communicate with the output chamber F,
The effective area (first area) where the output air pressure acts as a balancing force is 9, and when the third solenoid valve MV5 is excited, one balancing chamber C5 is opened to the atmosphere, so the output air pressure is The effective area (second area) that acts as a balancing force is switched to six.

This third solenoid valve MV5 is energized when the running speed of the train exceeds a first high-speed set value (for example, 110 km/h), and the third solenoid valve MV5 is energized when the running speed of the train exceeds a high-speed first set value (for example, 110 km/h), and the third solenoid valve MV5 is energized when the running speed of the train exceeds a high-speed first set value (for example, 110 km/h), and the third solenoid valve MV5 is energized when the running speed of the train exceeds a high-speed first setting value (for example, 110 km/h).
It is set to demagnetize when the speed drops below a set value (for example, 40 km/h).

In the first embodiment shown in FIG. 1 above, the operation when the third solenoid valve MV5 is demagnetized is the same as that shown in FIG. 7, and is as shown in Table 1 above. Furthermore, the operation when the third solenoid valve MV5 is excited is basically the same as shown in Fig. 7, but the increased output air pressure is 1 notch (1/6), 2 notches (2/6 ).

3 notches (3/6), 4 notches (4/6), 5 notches (
5/6), 6 notch (6/6), 7 notch (7/6),
8 notches (9/6), emergency (9/6).

In addition, each solenoid valve MVI to MV3 in the first embodiment
．． MV5. It is optional whether the EBV is set to a constantly demagnetized type or a constantly energized type.

Moreover, the installation position of the third throttle NV3 may be the exhaust port Ex or the supply/discharge port of the third solenoid valve MV5, or this may be deleted.

Furthermore, the area ratio of each piston S1 to S5 may be changed as necessary.

Fig. 2 shows the second embodiment (decompression type), which differs from the first embodiment shown in Fig. 1 in that the area ratio of the balancing pistons S4 and S5 is set to S4:55 = 9:11. Other details are the same as in Figure 1.

Therefore, in this second embodiment, the third solenoid valve MV
5 is energized, its reduced output air pressure is 1
Notchi (1/11), 2 Notchi (2/11), 3 Notchi (3/11), 4 Notchi (4/11), 5 Notchi (
5/11), 6 notch (6/11), 7 notch (7/
11), 8 notches (9/11), emergency notches (9/1)
1).

FIG. 3 shows a third embodiment (pressure increase type), which differs from the first embodiment shown in FIG. 1 in that a fourth partition wall V is provided between the balancing pistons S4. One balancing chamber C5 is formed between the piston S4, and the space between the fourth partition wall V and the balancing piston S5 is opened to the atmosphere.
Another balancing chamber C6 is provided between the partition wall Q, and these balancing chambers C5 and C6 are connected to the output chamber F via a constantly excited fourth solenoid valve MV6 with 4 ports and 2 positions. It is.

Since this fourth solenoid valve MV6 is normally excited, it is switched to the first position (a), communicating the output chamber F with one balancing chamber C5 and the other balancing chamber C6 with the atmosphere. When the pressure is increased, it is demagnetized and returns to the second position (b), communicating the output chamber F with the balance chamber C6 and opening the balance chamber C5 to the atmosphere.

The other configurations and operations of the third embodiment shown in FIG. 3 are the same as those shown in FIG. 1, so their explanations will be omitted.

FIG. 4 shows a fourth embodiment (pressure increase type), which is different from the first embodiment shown in FIG. This is because the area ratio of the balancing piston 36.35 is S6:55=3:6, and other explanations will be omitted.

FIG. 5 shows a fifth embodiment (m pressure type), which is different from the second embodiment shown in FIG. Balance piston S6. The area ratio of S5 is S6:55=2:1
1, and other explanations will be omitted.

FIG. 6 shows a sixth embodiment (decompression type), which differs from the fifth embodiment in FIG.
The additional position of C5 is reversed, and the area ratio of the balancing pistons S6 and S35 is S6:55 = 2:9, and the balancing chamber C5 is normally open to the atmosphere, and when depressurizing, the balancing chamber C5 is opened to the atmosphere. This is the point of introducing the output air pressure into C5, and other explanations will be omitted.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the first embodiment (pressure increase type) of the present invention,
Fig. 2 is an explanatory diagram of the second embodiment (pressure reduction type), Fig. 3 is an explanatory diagram of the third embodiment (pressure increase type), and Fig. 4 is an explanatory diagram of the fourth embodiment (pressure increase type). 5 is an explanatory diagram of the fifth embodiment (reduced pressure type), FIG. 6 is an explanatory diagram of the sixth embodiment (reduced pressure type), FIG. 7 is an explanatory diagram of the conventionally known example, and FIG. The figure is an explanatory diagram of another conventional example (not publicly known). DRV...Multi-stage relay valve MR...Pressure air source BC/
... Brake cylinder D ... Air supply chamber E ... Exhaust chamber F ... Output chamber H ... Air supply hole I ... Valve seat J.
...Return spring K...Air supply valve M...Exhaust valve stem R.
...Return spring SL, S2. S3...First control piston S4...Control (balance and second control) piston S5. S6...Balancing piston Applicant: Japan Air Brake Co., Ltd. $+ concave

Claims (1)

[Claims] (1) An air supply chamber connected to a pressurized air source, an output chamber connected to a brake cylinder, an exhaust chamber open to the atmosphere, and an air supply hole that communicates the air supply chamber with the output chamber. a valve seat protruding around the side; an air supply valve biased by a spring so as to be seated on the valve seat; A hollow exhaust valve rod with one opening at the tip and the other opening into the exhaust chamber, and a command force that receives pressurized air and moves the exhaust valve rod toward the air supply valve in response to a brake command consisting of a digital electric signal. a plurality of control pistons that receive pressurized air in the output chamber and receive a balancing force that opposes the command force, and outputs air at a pressure that corresponds to the brake command. The relay valve is characterized in that the effective area on which the output air acts as a balancing force on the balancing piston is switched between a normal first area and a second area that is larger or smaller than the normal first area. Multi-stage relay valve for vehicles.