CZ28918U1 - Pipe accelerator of air brakes of rail vehicles - Google Patents

Description

Technical field

The object of the present invention is to provide a pneumatic brake accelerator for rail vehicles.

Background Art

A pipe accelerator is a device for increasing the rate of air pressure drop in a main train pipe, a set of railway vehicles. It may be part of a braking device of a railway vehicle where, by increasing the pressure drop propagation, it accelerates the response of the vehicle's braking system to the driver's instruction, thus shortening the train's braking path and thereby increasing the safety of the railway operation. The line accelerator must respond to a defined pressure drop in the main train line. If there is a sudden drop in pressure in the main pipe, ie emergency braking, the pipe accelerator must respond to this sudden pressure drop in the main pipe. It must additionally support a rapid reduction of the main pipe pressure to below 2.5 bar. The pressure drop in the main pipe to which the pipe accelerator must react is defined as a drop from a 5 bar operating pressure to 3.2 bar for a 3 s (or less) time. For this drop, the pipe accelerator must respond within 2 seconds and begin to discharge air from the main pipe to the surroundings. At the same time, the line accelerator must stop this drain below 2.5 bar, so that the main line can be filled more quickly again.

The line accelerator must not respond to other pressure drops in the main train line. If there is a gradual pressure drop in the main pipe, ie service braking, the pipe accelerator must not react to this drop in the main pipe. This drop is defined as a drop from a 5 bar operating pressure to 3.2 bar for 6 s (or greater). In the case of such a decrease, the pipe accelerator must not react up to a value of 2 bar in the main pipe. The Pipe Accelerator must not operate during a severe pressure drop in the main pipe following a pressure increase above the operating value. Overcharging is defined by increasing the pressure to 6 bar for 2 s, followed by a steep drop to 5.2 bar in 1 s.

The pipe accelerator comprises a control chamber which is connected by a calibrated nozzle to the main pipe of the railway vehicle at the inlet. A plunger with a plunger is disposed against the undesired increase in pressure in the control chamber. Further, the pipe accelerator includes an acceleration flap and a discharge flap that are actuated by adjacent springs and lifting pins.

The disadvantage of the current state of affairs is, in particular, the increased volume of the control chamber and thus the entire pipe accelerator.

The essence of the technical solution

The aim of the present technical solution is to fulfill all the above described requirements.

It is an object of the present invention to provide a pneumatic brake accelerator of a train rolling stock comprising a body adapted to be coupled to a main train line, the body comprising means for controlling a main air intake manifold and including a control chamber adapted for connection with this main pipe. These means consist of a plurality of interconnected channels formed in the body and closable, depending on the train braking mode used, by means of shut-off valves actuated by pistons and pins, by springs housed in the body cavities, in cooperation with the outlets. control chamber.

The essence of the technical solution is that the control chamber is formed directly in the body at the inlet of the main pipe, and is connected to the main pipe via a set of two calibrated nozzles of substantially identical cross-section, located one after the other in the inlet channel of the body.

- 1 CZ 28918 Ul

The nozzle inner diameter is preferably less than 0.5 mm.

This arrangement makes it possible to reduce the volume of the control chamber to a value of less than 0.5 liters, while maintaining conventional manufacturing techniques of calibrated nozzles. The volume of the chamber, which is an integral part of the body of the pipe accelerator, is designed within the body of the pipe accelerator so that its external dimensions can be regular and minimal.

The main conduit is first connected to the inlet to the control chamber at the inlet to the housing, and at the same time as the space above the control chamber, that is, the space below the acceleration valve, and also the connecting channel through the second calibrated opening with the chamber of the second piston located in the housing at the air outlet. and at the same time, via an acceleration flap provided with an opening, with a space formed along the length of the body to the outlet of the compressed air outward. The space between the acceleration flap and the drain flap is connected via a calibrated air hole. In front of the air outlet, a discharge flap is located in the space above the second piston chamber, and the opening and closing strokes of the acceleration flap are adapted to control the pressure changes in the control chamber, and the opening and closing strokes of the discharge flap are adapted to control the chamber pressure with the second piston, after the second calibrated hole. Further, the control chamber is connected by a second channel and a third air outlet channel through a protective valve whose opening and closing strokes are also controlled by the pressure in the control chamber.

In the control chamber, a diaphragm is mounted with a first piston loaded against overpressure in the control chamber by the first force of the first springs located above it. A first pin slidably guided in the body is supported on the first piston, the opposite end of which is supported on the bottom by an acceleration flap, also loaded against overpressure in the control chamber by the pressure of the second spring, which holds the acceleration flap in the closed position. The thrust force of the second spring is adjustable by means of an adjusting screw located in the body of the accelerator.

By adjusting the force of the second spring by the adjusting screw, it is possible to accurately respond to the time course of the pressure difference dp between the main pipe and the control chamber of the pipe accelerator during the discharge of the main pipe. Thus, the point of reaction of the acceleration valve is controlled by the adjusting screw. It is also possible to eliminate the manufacturing deviations of the calibrated nozzles and the first and second springs and to fine tune the parameters of the entire apparatus.

In the space behind the acceleration flap in the direction of the outlet opening of the pipe accelerator, there is a discharge flap, which is loaded by the thrust force of the third spring against the pressure of the second pin slidably guided in the body, where the opposite end of the second pin abuts the second piston, guided in the body chamber, connected the first channel through the second calibrated opening with the main pipe.

The protective flap is arranged in the housing cavity in a closed position by its mounting on a thrust fifth spring below the third piston, which is pushed out by its fourth spring, whereby a second channel connecting this space to the main conduit opens into the space above the third piston for the opening stroke of the protective flap . Furthermore, a third channel extends from the space below the third piston, ie from the space above the protective valve, connected to the air outlet from the body of the accelerator. All of the shutters are plate-like housings housed in a body of the accelerator with the possibility of sliding movement and adapted in the closing position of the shutters to fit the seats, formed in this body.

To stop the discharge of the compressed air from the main pipe through the duct or duct. the space between the acceleration flap and the discharge flap and the outlet of the duct accelerator into the atmosphere occurs when the discharge flap is closed by the force of the third spring and due to the leakage of compressed air from the main conduit acting on the second piston by the second calibrated aperture and the first conduit. The control chamber is connected via a second compressed air channel to a chamber of a third piston acting against the force of the fourth spring on a valve seated on a fifth spring, the pressing force of which acts against the force of the fourth spring, wherein in the functional position of the open valve, the third piston exceeds the forces of the fourth spring and a fifth spring, the control chamber is connected by a third channel to the outlet opening of the pipe accelerator. This arrangement prevents the pressure in the control chamber from increasing to an undesirable value.

-2CZ 28918 Ul

Clarifying drawings

The accompanying drawings show an exemplary embodiment of the present invention. Fig. 1 is a schematic diagram of a pipe accelerator arrangement; Fig. 2 is a vertical sectional view of an assembly of two calibrated nozzles arranged one behind the other in a channel between the main pipe and the control chamber.

3 to 6 show an axonometric view of an embodiment of a pipe accelerator. Fig. 7 is a graph of the time difference of the pressure difference dp between the main pipe inlet pressure and the pressure in the control chamber of the pipe accelerator.

Examples of technical solutions

A control chamber 2 is formed in the body of the duct accelerator, the inlet of which is a main line 1 of the air inlet pressure HP. The control chamber 2 is connected to this main conduit 1 by means of two consecutive calibrated nozzles 7. The conduit accelerator further comprises an acceleration valve 8 and a discharge valve 12 which are actuated by adjacent springs 10, 13 and 21 and by lifting pins (first pin 6 and second pin). pin 14).

In the control chamber 2, a first piston 3 is provided with a diaphragm 4, on which the first spring 5 abuts and permanently presses it inwardly into the control chamber 2. The first piston 3 is further facing the first piston 3, the opposite end of which faces the acceleration valve. 8, which is located under the second spring 10. The thrust force of this second spring 10 is controlled by an adjusting screw 9 which extends into the space 25 with an acceleration valve 8 and a drain valve 12 and which connects the inlet of the accelerator pipe (main pipe 1) with its outlet opening 15.

The space above the first piston 3 below the acceleration flap 8 is connected to the inlet of the accelerator (main pipe i) and, on the other hand, is connected by the first duct 18 via the second calibrated opening 17 to the chamber below the second piston. , at the opposite end of which the discharge valve 12 is loaded by the thrust force of the third spring 13, with the possibility of interconnecting the space 25 with the acceleration valve 8 and the discharge valve 12 and thus the inlet of the pipe accelerator (main line 1) with its outlet opening 15 or closing the connection. Further, the duct accelerator control chamber 2 is connected via a second duct 23 to a third piston 20, which acts against a protective flap 22, which is mounted on the fifth spring 21, against the wall of the third piston 20, against the wall. the control chamber 2. The flap 22 and the third piston 20 protect the control chamber 2 against undesired increase in air pressure.

The pipe accelerator arrangement has the following functions.

1) Standby - filling the accelerator pipe.

At the 0 bar main line inlet pressure, all three flaps 8, 12 and 22 are closed by the adjacent springs 10, 13, and 21. The first spring 5 displaces the first piston 3 with the diaphragm 4 downward and thus the first pin 6 is not in the fourth spring 19 lifts the third piston 20 and is no longer in contact with the shutter 22. The third spring 13 over the dispensing flap 12 and the second pin 14 presses the second piston 16 downward. As the inlet pressure in the main conduit 1 begins to rise, the pressurized air 7 enters the control chamber 2 through the calibrated nozzles 7. The compressed air fills the space under the acceleration valve 8 around the first spring 5 and the first pin 6 and at the opening in the acceleration valve 8 and the space above the valve. around the second spring 10. At the same time, the compressed air flows through the first passage 18 through the second calibrated opening 17 into the space of the second piston 16. Here, at a value of about 3 bar, the force on the second piston 16 overcomes the force of the third spring 13 and the drain valve by the second pin 14 and the drain valve 12. 12 is thus moved to the open position. The space 25 between the shutters 8 and 12 is connected to the discharge outlet 15 and 15, respectively. with the air. At the same time, this space 25 is connected to the air by the first calibrated opening 11. The pressurized air in the control chamber 2 also flows through the second channel 23 above the third piston 20. However, the piston remains at the same operating pressure as the fourth spring 19. still closed by the force of the fifth spring 21.

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2) Service braking - the pipe accelerator does not start operation.

During train service braking, the main line I pressure drops from standby pressure of 5 bar to 3.5 bar. This drop occurs at such a rate that the compressed air in the control chamber 2 chases through the calibrated openings or the openings. Partially flowing the nozzles 7 back into the main conduit 1. The resulting pressure difference between the air pressures in the main conduit I and the control chamber 2 when acting on the diaphragm 4 and the first piston 3 does not overcome the forces of the springs 5 and 10 and thus does not open the acceleration valve. the flaps 12 and 22 remain unchanged. The pipe accelerator does not start up when the air pressure in the main pipe drops.

3) Quick-acting braking - the pipe accelerator starts operation.

During rapid train braking, the pressure in the main pipe decreases even from the 5 bar standby pressure. This drop occurs at a higher speed than in service braking, and therefore the compressed air in the control chamber 2 does not withstand the calibrated orifices. The resulting pressure difference between the main pipe pressures and the control chamber 2 when acting on the diaphragm 4 and the first piston 3 overcomes the forces of the springs 5 and 10 and the acceleration valve 8 is opened. . The pressurized air from main conduit 1 begins to flow very quickly through the channel / space 25 between the acceleration flap 8 and the discharge flap 12 and under the open discharge flap 12 through the vent outlet 15 into the atmosphere. During this discharge there is a rapid drop in the air pressure in the main pipe 1. At the same time, pressurized air, acting on the second piston 16, flows through the second calibrated hole 17 and the first channel 18 back into the main pipe 1. As soon as the air pressure in the main conduit 1 and / or the main conduit 1 flows into the main conduit. below the second piston 16, it drops to 2 bar, the force of the third spring 13 overcomes the force on the second piston 16 by the discharge valve 12 and the second pin 14, thereby closing the drain valve 12. This discharges the air in the main pipe 1. After this closure of the dispensing flap 12 further results in a noticeable discharge of air from the main conduit 1 or the conduit 1, respectively. During the discharge of air pressure from the main conduit even after the discharge has been completed by closing the dispensing flap 12, the air from the control chamber 2 escapes continuously through the calibrated orifices. By reducing the difference of these two pressures, the acceleration flap 8 is again closed due to the forces of the springs 5 and 10. After closing the acceleration flap 8, the space 25 is fully vented through the first calibrated hole 11. standby. During the operation of the pipe accelerator, the position of the valve 22 is not changed.

4) Pipe Accelerator Protection with Filling Swing.

If the filling stroke is introduced after braking, the main line pressure 1 will increase rapidly above the operating pressure of the accelerator pipe. The pressurized air from main line 1 starts to flow through the calibrated holes or the openings. through the nozzles 7 into the control chamber 2 and also through the second channel 23 into the space of the third piston 20. As soon as the air pressure in the control chamber 2 and hence in the second channel 23 and the second channel 23, respectively. in the space of the third piston 20 rises above the critical value, the force of the compressed air on the third piston 20 overcomes the forces of the fourth and fifth springs 19 and 21 and lifts the flap 22. The pressurized air will escape under the flap 22 into the third duct 24 and thereby into the vent outlet 15 , respectively. into the air. The increase in the pressure in the control chamber 2 is thereby stopped and, after completion of the filling swing and the subsequent abrupt drop in the air pressure in the main pipe 1, the pipe accelerator is not activated. When the air pressure in the control chamber 2 is again reduced, the shutter 22 closes in that the forces of the springs 19 and 21 override the force on the third piston 20. Thus, the discharge of the pressurized air from the control chamber 2 is terminated.

Claims (8)

PROTECTION REQUIREMENTS Arrangement of a pneumatic brake pipe accelerator of a train of a train, comprising a body (26) adapted to be connected to a main pipe (1) of a train set (1), wherein the body (26) comprises means for controlled connection of the main pipe (1). an inlet air having an air outlet (11, 15) and comprising a control chamber (2) adapted to communicate with said main duct (1), and wherein said means consist of a system of interconnected ducts formed in the body (26) and closable, depending on the braking mode used in the train set, by means of the closing valves operated via pistons and pins, by means of springs housed in the cavities of the body (26), in cooperation with the outputs from the control chamber (2), characterized in that the chamber (2) is formed directly in the body (26) at the inlet of the main pipe (1), and is connected to the main pipe (1) via six and in two calibrated nozzles (7) of substantially identical cross-section, located immediately after each other in the inlet duct of the body (26). A pipe accelerator arrangement according to claim 1, characterized in that the inner diameter of the nozzles (7) is less than 0.5 mm. A pipe accelerator arrangement according to claim 1 or 2, characterized in that the main pipe (1) is connected at the inlet to the body (26) first with the inlet to the control chamber (2) and simultaneously with the space above the control chamber (2). with the space under the acceleration flap (8) as well as the connecting channel (18) through the second calibrated bore (17) with the chamber of the second piston (16) situated in the body (26) at the air outlet (15) and simultaneously an opening provided with an opening (25) formed along the length of the body (26) up to the outwardly directed compressed air outlet (15), wherein the space between the acceleration valve (8) and the discharge valve (12) is interconnected by means of a calibrated orifice (11) with air, and wherein, prior to the air outlet (15), a discharge valve (12) is situated in the space (25) above the second piston chamber (16), the opening and closing strokes of the acceleration valve (8) being adapted for o controlled by varying the pressure in the control chamber space, and the opening and closing stroke of the discharge valve (12) is adapted to be actuated as a function of the pressure in the chamber with the second piston (16), behind the second calibrated bore (17); 2) interconnected by a second duct (23) and a third duct (24) with an air outlet (15) via a protective flap (22) whose opening and closing stroke is also controlled by pressure in the control chamber (2). A pipe accelerator arrangement according to claim 3, characterized in that a diaphragm (3) with a first piston (4) loaded against overpressure in the control chamber (2) by a thrust force placed above the first spring (5) is mounted in the control chamber. the first piston (4) is supported from above by a first pin (6) displaceably guided in the body (26), the opposite end of which rests on the underside of the acceleration flap (8) also loaded against overpressure in the control chamber (2) ) which holds the acceleration flap (8) in the closed position. Pipe accelerator arrangement according to claim 4, characterized in that the contact force of the second spring (10) is adjustable by means of an adjusting screw (9) situated in the pipe accelerator body (26). Pipe accelerator arrangement according to one of Claims 3 to 5, characterized in that the discharge valve (12) is loaded by a thrust force of the third spring (13) against the pressure of the second pin (14) slidably guided in the body (26), the end of the second pin (14) abuts the second piston (16), guided in the body chamber (26), connected by the first channel (18) through the second calibrated bore (17) to the main pipe (1). Pipe accelerator arrangement according to one of Claims 3 to 6, characterized in that the protective flap (22) is arranged in the cavity of the body (26) in the closed position by its mounting on the pressure fifth spring (21) below the third piston (20). which is pushed by means of its fourth spring (19), for opening the protective flap (22), a second channel (23) connecting this space with the main pipe (1) and into the space below the third piston (20) through a third piston (20), i.e. from the space above the protective flap (22), extends a third duct (24) connected to the air outlet (15) from the pipe accelerator body (26). Pipe accelerator arrangement according to one of Claims 3 to 7, characterized in that all the flaps (8, 12, 22) are plate-shaped bodies housed in the pipe body (26) of the pipe accelerator with sliding motion and adapted in the closing position of these flaps (8, 12, 22) for engaging the seats formed in the body (26).