CH621297A5 - Pressure distributor for the brakes of a vehicle - Google Patents

Description

The present invention relates to a pressure distributor for the brakes of a vehicle, such as a pneumatic distributor with two-position vacuum-charged device used for controlling the braking of railway vehicles.

In the braking devices of railway vehicles, the brake pressure distribution valve called "distributor or triple valve" has a main device, which is composed of a diaphragm control unit and a pressure reducer. The control crew reacts according to a pressure difference occurring between the fluid in the general pipe and that of a pressure-control tank, which difference is exerted on an action section, in order to control the pressure reducer, which s balance by the admission, on a reaction section, of the outlet pressure applied to the brake cylinders of the railway vehicle.

When the rail brake distributors are provided with a vacuum-loaded device, either this device constitutes a separate relay from the main device, or it is annexed to the main device. In the first case, the relay is quite bulky and requires a modification of the distributor body or the release of a large volume on the side of the body; in the second case, it is very difficult to respect the times recommended by the International Union of Railways or the railway networks for the supply and exhaust of the brake cylinders because we admit in these cylinders a different pressure when empty and loaded and there is a risk of derailments occurring when the brakes are applied or coupling breakage during the release of the brakes.

The object of the invention is in particular to respect, in a pneumatic brake distributor with several brake pressure ranges such as empty-loaded for railway vehicle with two braking powers, the brake application and release times for each of the two brake pressure ranges while keeping the modification or size of the distributor small and without adding a pressure relay valve or pilot capacity for the "application" and "release" times of the brake.

To this end, the pressure distributor for the brakes of a vehicle, in particular of a railway vehicle, of the type comprising a main pressure reducing valve, the action and / or reaction surface of which comprises at least two parts, one of which is likely to be subjected to pressure as a function of a variable vehicle parameter, is characterized in that a device for adapting the braking times and / or the brake release times is provided between the pressure source regulator and

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less capacity of the brakes supplied by the regulator and / or between this capacity and the exhaust, and in that the adaptation device comprises at least one adaptation member capable of being automatically put into service by a switching member controlled according to the parameter.

Advantageously, the device comprises, in a body, a main regulator unit and a switch making it possible to control at least two ranges of speed of increase and / or descent of the braking pressure as a function of a parameter of the vehicle, and the main crew comprises a regulator supplied by a source of pressurized fluid and piloted by a rod mechanically linked to an action and reaction piston capable of causing the communication of at least one brake cylinder of the vehicle with the source of fluid under pressure or respectively with the discharge, or else to cause the isolation of the brake cylinder in response to the action of a control pressure constituted by the pressure difference between a general braking line and a pressure reservoir, acting on an action surface of the piston and respectively on the action of the outlet pressure of the regulator addressed to the brake cylinder and acting on a reaction surface, the surf ace of action and / or the reaction surface being divided into parts of different sections according to the braking range and the switch controlling the connection of these parts with the control pressure, or respectively with the outlet pressure of the regulator, by means a brake range selection valve actuated manually or automatically depending on the desired range, in particular depending on the load, the distributor being then characterized by the fact that for each pressure range, is automatically interposed between the regulator and the brake cylinder, a member for adjusting the supply times of the brake cylinder comprising at least one calibrated orifice or throttle called "clamping" for adjusting the speed of supply of the brake cylinder by the pressure reducer and / or is interposed automatically between the brake cylinder and the exhaust, a member for adapting the exhaust times of the brake cylinder comprising at least one orifice cali break or a so-called "release" throttle for adjusting the bleeding speed of the brake cylinder via the pressure reducer, these adapters for the "application" and respectively "application" times being different for each range and each speed of braking pressure and respectively put into service automatically as a result of the actuation of the selection valve, the passage sections of said throttles for each range and each braking regime being chosen as a function of the maximum braking pressure provided for the braking range with a view to obtaining, for the various pressure ranges of the same braking regime, durations of rise and / or respectively descent of the braking pressure to the vicinity of this maximum or respectively from the neighborhood of the maximum braking pressure which are substantially equal, that is to say the same "application" times and the same "release" times for the various pressure ranges of the same diet.

According to an advantageous embodiment of the subject of the invention, the adaptation members of the "tightening" and "loosening" times comprise an adaptation valve comprising a throttle valve controlled by a piston urged to against a return spring in the direction of closing of said valve by the pressure delivered by the selection valve for the low braking power of the range, the piston carrying a by-pass to the throttle valve an orifice calibrated supply and a calibrated exhaust port mounted in series, the exhaust port being carried by a non-return valve which opens in the direction of supply of the brake cylinder or being mounted in parallel with this valve non-return.

The calibration of the piston return spring can be such that the throttle valve does not close under the action of the pressure delivered by the regulator until after this pressure has reached a

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minimum value known as "first time" below which the brake cylinder is supplied at high flow rate by the regulator.

In the case where there is already provided in the brake pressure distributor a “first time” valve placed at the outlet of the regulator, the adaptation valve can be placed in the brake distributor between the brake cylinder and the valve "First time" connected to the outlet of the regulator and the calibration of the piston return spring can be such that the throttle valve closes under the action of the pressure delivered by the regulator via the selection valve for a value of this pressure (also supplying the brake cylinder) substantially equal to that causing the closure of the "first time" valve and the interruption of the high-flow connection between the regulator and the brake cylinder for the "first time" pressure time ”capable of overcoming the restoring forces and friction of the brake linkage before starting the effective braking of the vehicle, so as to allow the high-speed“ first time ”supply of the brake cylinder as well for the high pressure of the range than for the lower pressure of the range delayed by the throttle valve after the "first time" pressure.

When the distributor comprises a control member with two tightening-loosening regimes such as the “goods-travelers” or “GP” lever, two adaptation valves with orifices calibrated in series can be mounted in parallel and are assigned one to “passenger” operation and the other to “goods” operation and are mechanically connected to the “goods-traveler” lever ensuring manual or automatic switching from one tightening-loosening regime to the other.

One of the two calibration valves with calibrated orifices can be replaced by the series connection of two calibrated orifices, the smallest of which is carried by a non-return valve - or located on this valve - which opens in the direction of the 'supply to the brake cylinder, these calibrated orifices being placed on a bypass that can be closed off by the “goods-passenger” valve (GP) between the outlet of the regulator and the other remaining adaptation valve.

The selection valve is actuated mechanically by means of a linkage or direct manual action, or else in other embodiments, the selection valve is actuated by a fluid pressure depending on the load of the vehicle or d '' another parameter of the vehicle (speed for example). The selection valve can be actuated remotely by means of an electrical signal for change of range and / or braking speed.

According to another advantageous embodiment of the object of the invention, one of the parts of the reaction surface consists of a diaphragm piston which is housed in a flange attached to an ordinary distributor body provided at the origin for a single section of the reaction surface. The selection valve and the throttling members are then housed inside the flange or attached to an external face of the flange to create with it a removable sub-assembly for a standard brake distributor originally intended for a single braking regime.

Aims, advantages and characteristics of the invention will appear better on reading the description which follows, given with reference to the attached drawing by way of nonlimiting examples, and where:

Fig. 1 shows in elevation a pneumatic rail brake distributor according to the invention, with a part of its control support tank;

fig. 2 to 4 are developed diagrams of several embodiments of the dispenser according to the invention;

fig. 5 shows an embodiment of the adaptation valve;

fig. 6 shows an embodiment of the selection valve.

In fig. 1, there is shown a distributor which is fixed to its reservoir-control support RC. This distributor mounted on a rail vehicle to control the brake pressure of the vehicle comprises a main casing 3, a lower cover 4

and between these two parts an intermediate flange - or plate - 5. The elements 3, 4, 5 are secured by means of screws 6. The intermediate plate internally has an auxiliary reaction chamber and an adaptation device and it carries externally s a reversing valve 20, but the latter can of course also be integrated. We also see in fig. 1 a lever 7 for reversing “goods-travelers” (GP) located behind the distributor and making it possible to turn a ball valve to modify, depending on the type of vehicle, the supply and exhaust times of the brake cylinders.

It is useful to recall briefly that the distributor shown has the essential object of delivering to the brake cylinders CF by means of a main device an increasing pressure as a function of the drop in fluid pressure in a general pipe CG is with respect to the control tank. RC. The general line passes through the control tank and makes it possible to supply the latter by a nozzle not shown and by a filling valve integrated in the distributor.

The various valves contained in the body 1 of the dispenser are illustrated by the diagram developed in FIG. 2; those which are not strictly necessary for the description have been simply outlined in phantom.

The valves comprise: a main device 10, a valve 11 for accelerating the application of the brake, a valve 12 for re-pleating for an auxiliary tank RA and for a control tank RC, a valve 13 called “first time” , a device 14 for manual and automatic draining of the tanks, a non-return valve 15 protecting the auxiliary tank and a goods-passenger (GP) valve 16 operable by means of the lever 7. 30 The main device comprises a diaphragm unit 101 provided for actuating a regulator 102, a constant pressure chamber 103, a chamber 104 connected to a general line (CG), a chamber 105 connected to the atmosphere and a reaction chamber 106 connected to the brake cylinders (CF); the ordinary reaction section of the main device 10 is designated by Si. On the other hand, the “first time” valve 13 has a high flow passage which can be closed off by a valve as soon as the presumed pressure reached at the brake cylinders exceeds a certain threshold and has in parallel with the passage to .40 high flow a throttle which regulates the supply in the effective braking phase; the valve 13 practically does not intervene in the “travelers” position of the valve (G-P) because the latter then opens a bypass to said valve. In fact, when the vehicle braking is set to “passenger” speed for a short train, the braking pressure can increase or decrease quickly without risk of incidents.

The distributor also comprises a vacuum-charged device provided with:

a) an auxiliary reaction section S2 added to the control unit 50 of the main device 10, the auxiliary reaction section being created according to the embodiment represented by the use of an additional diaphragm and of a auxiliary reaction chamber 107 located between chambers 105 and 106;

55 b) a reversing valve 20 controlled as a function of the load to allow the pressure delivered by the regulator 102 to apply when empty, but not to request on load, the auxiliary chamber 107 and therefore the auxiliary section S2 ;

c) a device 30 for adapting the supply and exhaust times of the brake cylinders, this device being located on the control chain which connects the main device 10 to the brake cylinders CF and those -this in the atmosphere and being switchable from an empty position to a loaded position and vice versa as a function of the quantity which translates the load and 65 controls the reversing valve.

The reversing valve 20 is connected to the auxiliary reaction chamber 107 by a conduit 41 and to the adaptation device 30 by a conduit 42. A conduit 43 connects the adaptation device

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to the brake cylinders while a conduit 44 connects the same device 30 to a bifurcation connected to one or the other of the outputs of the “first time” valve 13. The connection between the conduits 42 and 44 is open at permanence while the switching 44-43 is controlled by the device 30 in a manner which will be described with reference to FIG. 5.

Firstly, it is worth recalling that, on an ordinary dispenser, the GP valve 16 includes two insulation elements 16a, 16b; the first element 16a controls the opening and closing of a duct 45 connecting the outlet of the regulator 102 to the duct 44 (closing in the “goods” position); the second element 16b controls the opening and closing of a conduit 46 connecting the brake cylinders via the main device to a calibrated exhaust orifice 47 to limit the exhaust to the only calibrated orifice 48 (closing in position "merchandise"). Similarly, the conventional supply of the brake cylinders is determined by means of a calibrated orifice 49 in the "passenger" position and in the effective braking phase by an orifice 50 of the valve 13 in the "goods" position. A calibrated orifice not shown may possibly be placed on the duct 45.

The adaptation device 30 (FIG. 5) comprises a valve 31 conforming to the upper part of a piston 32; the valve 31 makes it possible to cut the non-throttled connection between the conduits 41, 44 and 43, the piston 32 is biased in the direction of opening of the valve by a spring 33 and in the direction of closing by the pressure of the prevailing fluid in a pilot chamber 34 connected to the conduit 41; this pressure is that prevailing in the conduit 42 transmitted by the conduit 41 when the reversing valve 20 allows the connection between the conduits 41 and 42.

As soon as the valve 31 is closed, the adaptation device 30 intervenes by means of two calibrated orifices A, B, arranged in series. The orifice B is provided on a non-return valve 35 - or in parallel with it - said valve being pushed back into the closed position by a weak spring 36. The orifice A determines the feeding time and the orifice B, smaller , determines the exhaust time of the CF brake cylinders, because the valve 35 is closed in the direction of the exhaust.

In principle, the reversing valve 20 can be controlled in any way and can include a drawer or a double valve. The embodiment shown (fig. 6) comprises a double valve 21 controlled by a piston 22 subjected to an adjustable prestressed spring 23 so that the pressure of a weighing regulator DP or a suspension cushion, transmitted to a pilot chamber 24, drives:

a) below the adjustment threshold cutting the link 41-42 and venting the conduit 41;

b) above the threshold the isolation of 41 from the atmosphere and the establishment of the connection 41-42.

In the variant shown in FIG. 3, the adaptation device 30 comprises two valves 30P, 30G making it possible to regulate the “passenger” times respectively through the calibrated orifices Ap-Bp of the valve 30P and the “goods” times thanks to the calibrated orifices Ag -Bg of valve 30G. The valves 30P, 30G are arranged in parallel and a third element 16c of the valve GP 16 selectively connects the outlet of one or the other valve 30 to the brake cylinders CF. An intercommunication 70 provides the permanent link 42-44 and the conduit 41 opens into the chambers 34 of the two valves.

The diagram in fig. 4 has been obtained by a simplification of that of FIG. 3. The 30P “passenger” valve is eliminated and replaced by the series connection of a calibrated orifice A'p of supply and of a calibrated orifice B'p of exhaust, the latter being in parallel with a non-return valve. 80 - or arranged in this valve - which opens in the feed direction. The assembly A'p, B'p is disposed on the conduit 45 downstream of the regulator 102, of the element 16a and of the third element 16c of the valve GP, but upstream of the junction of the conduit 43 which connects the valve 30G brake cylinders. Thus, in the “travelers” position, a direct connection of the duct 45 with the brake cylinders is ensured.

In summary, it can be seen that the supply and exhaust times also called "tightening" and "loosening" times are determined for the "empty vehicle" position.

1) in “passenger” mode: for fig. 2 according to the detail (fig. 5) by A when tightening, B when loosening; for fig. 3 by Ap for tightening, Bp for loosening; for fig. 4 by Ag + A'p in parallel with tightening, B'p + Bg in parallel with loosening;

2) under the “goods” regime; for fig. 2, by A when tightening, B when loosening; for fig. 3 and 4 by Ag when tightening and Bg when loosening.

The diameters of the orifices A, B, Ag, Bg, Ap, Bp and A'p B'p are chosen in each case to obtain the times desired for the maximum braking pressure delivered during emergency braking. All of the above being valid for the no-load regime, it is understood that the supply and exhaust times under load are given, as already mentioned, by the usual calibrated orifices 47, 48, 49, 50 on the rail brake distributors. It remains to be specified that, even in a dual-use “freight-passenger” rail distributor, the reversing and adapting device of FIG. 2 provided that the supply and exhaust times (supplied once and for all by the calibrated orifices A-B) fall within the permitted intervals, both in “freight” and “passenger” mode. The case of fig. 2 of course applies to single-use "goods" or "travelers" distributors.

Modifications can be made to the dispenser described; in particular, the reversing valve can be controlled mechanically by means of a linkage, for example connected to the suspension or by means of direct manual action.

The control of the reversing valve can be electric and be carried out by means of any weighing signal. In all cases, the reversing valve and the adaptation device can be controlled in parallel by the weighing signal instead of being controlled in series as shown. The same valve or solenoid valve can combine the functions of the reversing valve and the adaptation device; this valve may include a drawer part and a valve part.

Instead of being a vacuum-charged device, the device shown can also be a device with more than two pressure ranges, for example as a function of speed (called “high power”) and can therefore have a reversing solenoid valve. It is obvious that a pneumatic distributor with three speeds could be produced by adding a valve or calibrated orifices for adaptation and appropriate conduits. Although the reversing valve has been shown attached externally to the body of the dispenser, it can be integrated into a flange already comprising the auxiliary reaction section and the adaptation device to create a vacuum-charged sub-assembly capable of be easily attached to an ordinary dispenser body. The reversing and calibrating device according to the invention can of course also be applied to brake distributors called “triple valves” still used for long trains such as those commonly encountered on the North American continent. In the “triple valves” the pressure tank is not a separate control tank such as the RC tank but quite simply the supply tank of the regulator 102. The control pressure of this tank decreases after braking, it is thus easier to cause the release of the brakes by raising the pressure of the CG general line. The main crew of the "triple valve" can be controlled according to the invention with regard to the sections

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additional action or reaction and throttles to comply with the standard "application" and "release" times for variable brake pressure ranges depending on the load and / or the speed of the vehicle.

The device described can be applied to a relay valve of a brake pressure distributor and can vary the reaction section and / or the action section of the regulator to cause the discontinuous change of brake pressure ranges.

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Claims (13)

621,297 CLAIMS 1. Pressure distributor for the brakes of a vehicle, in particular of a railway vehicle, of the type comprising a main regulator unit (10), the action and / or reaction surface of which comprises at least two parts, one of which is likely to be subjected to pressure as a function of a variable parameter of the vehicle, characterized in that a device for adapting (30) the application times and / or the release times of the brakes is provided between the source pressure (RA) of the regulator (102) and at least one capacity of the brakes (CF) supplied by the regulator (102) and / or between this capacity and the exhaust (47, 48), and in that the device d adaptation (30) comprises at least one adaptation member (31, 32) capable of being automatically put into service by a switching member (20) controlled as a function of the parameter. 2 2. A pressure distributor for the brakes of a vehicle according to claim 1 and comprising in a body (3) a main regulator unit (10) and a switch (7,16a, b, c) making it possible to control at least two ranges speed of rise and / or fall of the brake pressure as a function of a vehicle parameter, the main crew (10) comprising a pressure reducer (102) supplied by a source of pressurized fluid (RA) and controlled by a rod mechanically linked to an action and reaction piston capable of causing the communication of at least one brake cylinder (CF) of the vehicle with the source of pressurized fluid (RA) or respectively with the discharge (47 , 48) or to cause the brake cylinder (CF) to be isolated in response to the action of a control pressure constituted by the pressure difference between a general braking line (CG) and a pressure reservoir ( RC), acting on a surface of action of the piston and respectively at the action of the outlet pressure of the regulator (102) addressed to the brake cylinder (CF) and acting on a reaction surface, the action surface and / or the reaction surface being divided into parts of different sections according to the braking range and the switch (7,16a, b, c) controlling the connection of these parts with the control pressure or respectively with the output pressure of the regulator (102) by means of a selector valve (20) of the braking range actuated manually or automatically as a function of the desired range, in particular as a function of the load, characterized in that for each range of braking pressure is interposed automatically between the regulator (102) and the brake cylinder (CF ) a member for adapting (30P, G) the supply times of the brake cylinder (CF) comprising at least one calibrated orifice or throttle (A) called “clamping” for adjusting the supply speed of the cylinder brake (CF) by the regulator (102) e t / or is automatically interposed between the brake cylinder (CF) and the exhaust (47,48) an adaptation member (30P, G) of the brake cylinder (CF) exhaust times comprising at least one orifice calibrated or a throttle (B) called "release" for adjusting the bleeding speed of the brake cylinder (CF) via the regulator (102), these adapters (30P, 30G) of the "tightening" times and respectively "release" being different for each range and each brake pressure regime and respectively put into service automatically following the actuation of the selection valve (20), the passage sections of said throttles (A, B) for each range and each braking regime being chosen as a function of the maximum braking pressure provided for the braking range in order to obtain, for the various pressure ranges of the same braking regime, rise times and / or respectively lowering of the brake pressure to the neighborhood of this maximum or respectively from the vicinity of the maximum braking pressure which are substantially equal, that is to say the same times "of application" and the same times "of release" for the various ranges of pressure of the same diet. 3. Distributor according to claim 2, characterized in that the respective commissioning of the adaptation members (30P, G) is controlled by the outlet pressure of the selection valve (20), so that the switching of this valve (20) causes the corresponding switching of the "tightening" (A) and / or "release" (B) adaptation members for the change of range and / or braking speed. 4. Dispenser according to one of claims 1, 2 or 3, characterized in that the adaptation members (30P, G) of the "tightening" and "loosening" times comprise an adaptation valve (30) comprising a throttle valve (31) controlled by a piston (32) urged against a return spring (33) in the direction of closing of said valve (31) by the pressure delivered by the selection valve (20 ) for the low braking power of the range, the piston (32) carrying a by-pass to the throttle valve (31) a calibrated supply orifice (A) and a calibrated exhaust orifice (B) mounted in series, the exhaust port (B) being carried by a non-return valve (35) which opens in the direction of supply of the brake cylinder (CF) or being mounted in parallel with this non-return valve ( 35). 5 5. Distributor according to claim 4, characterized in that the calibration of the return spring (33) of the piston (32) is such that the throttle valve (31) does not close under the action of the pressure delivered by the regulator (102) only after this pressure has reached a minimum value called "first time" below which the brake cylinder (CF) is supplied at high flow rate by the regulator (102). 6. Distributor according to claim 5, characterized in that the adaptation valve (30) is placed in the brake distributor between the brake cylinder (CF) and a “first time” valve (13) connected to the outlet of the regulator (102) and the calibration of the return spring (33) of the piston (32) is such that the throttle valve (31) closes under the action of the pressure delivered by the regulator (102) via the selection valve (20) for a value of this pressure (supplying the brake cylinder (CF) substantially equal to that causing the closure of the "first time" valve (13) and the interruption of the high-speed connection between the regulator (102) and the brake cylinder (CF) for the "first time" pressure capable of overcoming the restoring forces and friction of the brake linkage before starting the effective braking of the vehicle, so as to allow the high-speed "brake cylinder" (CF) supply for both high and low power range recession only for the lower pressure of the range timed by the throttle valve (31) after the "first time" pressure. 7. Distributor according to any one of claims 4 to 6, comprising a control member with two tightening-loosening regimes such as the lever (7) "goods-travelers", characterized in that two adaptation valves ( 30P, 30G) with calibrated orifices (Ap, Bp-AG, BG) in series are mounted in parallel and are assigned one (30P) for "passenger" operation and the other (30G) for "goods" operation and are mechanically connected to the “goods-passenger” lever (7) ensuring manual or automatic switching from one tightening-loosening system to another. 8. Distributor according to claim 7, characterized in that in one (30P) of the two adaptation valves with calibrated orifices (A'p, B'p), the smaller (B'p) of the two said orifices is carried by, or located on, a non-return valve (80) which opens in the direction of supply of the brake cylinder (CF), these calibrated orifices being placed on a by-pass closable by the "goods" tap. -travelers "(16) between the outlet of the regulator (102) and the other adapter valve (30G). 9. Distributor according to any one of claims 2 to 8, characterized in that the selection valve (20) is arranged to be actuated mechanically by means of a linkage or direct manual action. 10. Distributor according to any one of claims 2 to 8, characterized in that the selection valve (20) is arranged to be actuated by a fluid pressure depending on the vehicle load and / or the vehicle speed . 10 15 20 25 30 35 40 45 50 55 60 65 11. Distributor according to any one of claims 2 to 8, characterized in that the selection valve (20) is arranged to be actuated by means of an electric signal for change of range and / or of speed braking. 12. Distributor according to any one of claims 2 to 11, characterized in that one of the parts of the reaction surface consists of a diaphragm piston which is housed in a flange (5) attached to a body ordinary distributor (3) originally intended for a single section of the reaction surface. 13. Dispenser according to claim 12, characterized in that the selection valve (20) and the throttling members are housed inside the flange (5) or attached to an outer face of the flange (5) to create with it a removable sub-assembly for a standard brake distributor originally intended for a single braking regime.