DESCRIPTION

The present invention refers to a device for automatically resetting the emergency brake in trains.

As it is known, nowadays there is a great need to be able to control a possible fire on board a train when going though a tunnel. At present railway accidents are becoming more frequent; some accidents are only minor while others unfortunately have catastrophic consequences.

The increase in accidents is due to the increase in number of passengers and therefore of trains, to the presence inside the carriages of fabrics which, even if fire retardant, in case of fire, release toxic emissions which are highly hazardous for passengers, to the greater speed of trains that favours the overheating of metal parts that can trigger or favour a fire and to the presence of a great amount of electrical equipment (air conditioning, automatic doors, static converters, electric heating pipes, etc) which makes modern trains more comfortable and faster but also more delicate and subject to short circuits or overheating of certain parts which can favour the start of a fire.

In view of what has been mentioned above there is a great need to increase the level of safety in trains to safeguard passengers, railway staff, trains and the environment.

In order to better assess the consequences and tackle them we have taken into consideration a situation in which a fire, even small, breaks out in a train going through a tunnel. The result is that there is enormous danger and that, in particular conditions, the consequences can be extremely serious.

The hypothetical case studied involved a train with twelve, sixteen carriages, therefore with the potential capacity of between seven and nine hundred passengers, in which at a certain stage of its journey a fire breaks out. The obvious reaction of many people would be to stop the train by pulling the emergency brake in order to get off the train to safety. If for example the fire was in the last carriages and the emergency brake was pulled at the start of a three of four kilometre long tunnel, or even longer (and there are many tunnels this long), the train would stop at least one kilometre inside the tunnel depending on its speed. If the emergency brake used was in the carriage where the fire broke out, then it would not be possible to reach the brake again to reset it and the train would not be able to move, thus causing incontrollable panic and chaos and practically leaving no way of escape for many people due to the fire, combustion emissions, restricted space in the tunnel and impossibility of emergency services to access the area.

The above mentioned situation is caused by the way the brakes in a train work. In fact a general conduit starts from the locomotive and is present in each carriage; when a train is composed, the various sections of the general conduit are connected to each other so that there is one single pipe through which the air passes at a set pressure to keep the brakes in a non-operating condition. To slow down the train, the driver simply lowers the air pressure in the general conduit and this reduction triggers a braking device that controls and activates a pneumatic system that moves the blocks on the wheels and slows down the train. The brakes are deactivated by increasing the pressure in the general conduit. The emergency brake works in a similar way. In fact by pulling a handle which can be found in each carriage air is released from the general conduit triggering the braking device described above, thus slowing down and stopping the train.

The brake can only be reset by railway staff by directly repositioning the pulled handle. It is necessary to reset the handle actually pulled, therefore if the handle is pulled in the carriage where there is the fire it cannot be reset and the train can no longer move with the consequences described above. In particular, with patent no. 1330064, the applicant has produced a device for automatically resetting the emergency brake which solves a large part of the problems described above. In fact, this device allows railway staff to have the train under control especially in critical situations so that it can be moved the distance necessary to exit a tunnel or move away from a dangerous situation. The device is basically made up of a braking handle, a rotary plate envisaged to rotate upon the command of the handle and of a couple of levers, a main piston envisaged to run inside a couple of chambers and envisaged to automatically reset the brake, a tank for the accumulation of the air to be used for resetting the device once triggered, connected to the general conduit that serves to brake the train and to supply control and resetting means.

The device described has highlighted certain problems related to the need to have one piece of equipment for each emergency brake point, for example one in each compartment with significant costs in terms of system and in view of the large amount of equipment to control and maintain.

Another problem that has been highlighted is related to the fact that when a train moves again after an emergency, all the other equipment has to be cut off to prevent any other passenger from pulling the emergency brake handle and stopping the train again. In fact, the train must exit the tunnel and must not remain in the tunnel with a fire on board for any reason.

The aim of the present invention is essentially to overcome the drawbacks of the commonly known technique by resolving the difficulties by means of a device for automatically resetting the emergency brake in trains that allows a train to always exit a tunnel without the possibility of stopping again once the emergency brake has been pulled. A second aim of the present invention is to create a device for automatically resetting the emergency brake in trains that allows the brakes to be reset automatically and not manually so that the train can be moved to exit a tunnel when there is a fire in the train and the emergency brake has been pulled.

A third aim of the present invention is to make available a device that is structurally simpler and more economical.

A further aim of the present invention is to make available a device capable of cutting off all the other emergency brakes, once one has been pulled until the train is out of the tunnel or safely away from a dangerous situation.

A further aim of the present invention is to create a device that can be installed in new and existing trains.

A still further aim of the present invention is to create a device capable of offering greater flexibility of use and therefore considerable safety for passengers, railway staff and the train.

A further, but not last, aim of the present invention is to create a device that is easy to produce, functional and structurally simple.

These and still further aims, which will better emerge in the description that follows, are essentially achieved by a device for automatically resetting the emergency brake in trains, as outlined in the claims that follow.

Further characteristics and advantages will better emerge in the detailed description of a device for automatically resetting the emergency brake in trains, according to the present invention, provided in the form of a non-limiting example, with reference to the accompanying drawings, in which: figure 1 shows, in a schematic view, a device for automatically resetting the emergency brake in trains in resting position; figure 2 shows in detail a first component of the device in figure 1 ; - figure 3 shows in detail a second component of the device in figure 1 ; figure 4 shows in detail a third component of the device in figure 1; figures 5A, 5B and 5C show, in a schematic view, respectively the device inserted in the braking system of a locomotive, pilot and train carriage;

- figures 6A, 6B and 6C show, in a schematic view, a variant of the device respectively inserted in the braking system of a locomotive, pilot and train carriage;

- figures 7A, 7B and 7C show, in a schematic view, another variant of the device concerned respectively inserted in the braking system of a locomotive, pilot and train carriage;

With reference to the above mentioned figures, 1 indicates a device for automatically resetting the emergency brake in trains, according to the present invention.

As mentioned previously, a train is usually made up of a locomotive, a number of carriages and a pilot carriage at the other end of the train compared to the locomotive which is used to control the train when the locomotive is pushing.

All passenger trains are equipped with a general conduit 100 and a main conduit 200 designed to contain compressed air and extend from the front of the train, including the locomotive, to the tail or last carriage.

More in detail, the general conduit starts from a brake control valve 101 and, as mentioned, extends to the last carriage as shown in figures 5A, 5B and 5C. Operating or standard pressure of the general conduit 100 is conventionally set at 5 bar.

Before using the train, the main tank 201 is charged using the compressor 700 present in the locomotive and then the brake tank 102 is charged and all the remaining components that are described below. Once the general conduit and the brake tanks are full, to brake the train it will be necessary to reduce the pressure by 5 bar by releasing air from the conduit while to release the brakes, the pressure in the general conduit must be increased by 5 bar. The operations mentioned above are carried out by the driver using the brake control valve

101 which is in the in both the front and rear driver's cabins in the locomotive and pilot carriage for remote control trains.

The main conduit 200 extends from the main tank 201 of the locomotive to the last carriage of the train as shown in figures 5 A, 5B and 5C. Operating or standard pressure of the general conduit 200 is of about 7.5 bar. The main conduit supplies the pneumatic facilities of the carriages such as, for example, the pneumatic control of the doors, supplies a large part of the capacity of the brake (auxiliary tank 203) and supplies the brake control valve 101 of the pilot carriage as shown in figure 5B.

As previously mentioned when a train is assembled, the various sections of the general conduit present in each carriage are connected to each other so that there is one single pipe through which the air passes supplied by the main tank 201 at a pressure of 5 bar to keep the brakes in a non-operating condition.

The device for automatically resetting the emergency brake 1 object of this document is essentially made up of three units.

A first power supply unit A envisaged to create or remove an airway between the general conduit and the second unit. The said first unit is supplied by the main conduit 200 and operates the pressure switch valve and is shown in figure 2. The device will include many first units, one for each carriage and one for the pilot carriage.

A second unit B, which is essentially the device illustrated in the previous patent of the

Applicant no. 1330064 with a significant modification which is described later, is shown in figure 3. The said second unit will be present in each carriage and in the pilot carriage.

A third activating unit C which is essentially constituted of an emergency brake activating handle and shown in figure 4. The said third unit will be present in each emergency brake activation point (for example one handle in each carriage compartment) in each carriage and the pilot carriage.

The said first power supply unit A, as mentioned, operates the pressure switch valve and is envisaged to cut off all the second units B and third units C of the train once the emergency brake has been activated. This valve is controlled and operated by the driver as described below.

In particular and as shown in figure 2 the said first unit A is composed of a first conduit 20 wherein a first end thereof has a valve R connected thereto which connects it with the train's general conduit 100 and the other end thereof is connected to a chamber 21 which links up the first conduit 20 and a second conduit 22, which is connected with the second unit B at the other end.

A piston 21a, located inside the chamber 21, envisaged to move and allow or prevent an airway from the first conduit 20 to the second conduit 22 depending on the pressure present in a small chamber 26. The said piston 21 which is equipped with a calibrated spring 23 housed in a seat 24 in the chamber 21 and envisaged to keep the piston facing the upper wall of the chamber so that the air can flow from the first conduit 20 to the second conduit 22. The seat 24 is equipped with a discharge hole 25 with a bleeding function to prevent air accumulating due to eventual draughts between the chamber 21 and the seat 24. It is obvious that any draughts would lead to alterations in the spring's duty 23.

Below the piston 21 there is the chamber 26, which constitutes a part of the chamber 21 to which is connected a third conduit 27 which is main conduit 200 of the train via valve Rl. When the pressure inside the small chamber 26 is above 6 bar, the said airway from the first conduit 20 to the second conduit 22 is created or is prevented when the pressure is under 6 bar, the said passage is prevented since the piston 21a is in a condition in which it can lower towards the lower part of the chamber 21 and then close the entrances of the first and conduit 20 and the second conduit 22.

According to the present invention, the said second unit B is essentially the device illustrated in the above mentioned patent. A description is detailed below for a better comprehension of the overall operation of the device concerned.

As shown in figure 3, the second conduit 22 is connected to the second unit B through channel 3a. Between the second conduit 22 and the channel 3a there is the air filter F. The said unit B consists of the tank 2 with he same pressure as the general conduit 5 bar envisaged for the accumulation of the air to be used for resetting the device, after its activation, a plurality of channels 3a, 3b, 3c, 3d and 3e and the non return valve 4 on channel 3a almost at the opening of the tank itself.

From the tank 2, a first channel 2a starts and arrives at a chamber 5, a second channel 2b arrives at a main piston 10, described below, and a third channel 2c which arrives at a small chamber 6a, in which there is a small piston 6.

The unit B includes the chamber 7 envisaged to reset the device after the emergency brake has been activated. In the chamber 7, the air coming from the tank 2 expands and causes the movement of the main piston 10 contained therein, thus resetting it to the non- operating condition shown in figure 1.

The air from the tank 2 flows into the second channel 2b, runs through a groove 8 with a calibrated hole 8a and continues along channel 8c up to channel 8d which arrives in the chamber 7 through the non return valve 80.

Between the channel 8c and the channel 8d, the device envisages a supplementary tank 2s. The air, following the path described from the tank 2 to the chamber 7, as it flows into the chamber 7, moves the main piston 10 from and operating to a non-operating condition. The movement of the piston 10 changes the position of the groove 8 so it is no longer in contact with the calibrated hole 8a so air can no longer pass through channel 8c to reach the chamber 7. The movement of the piston 10 not only causes the closure of the calibrated hole 8a but also the passage of air through the third channel 2c and the small chamber 6a into a channel 2d to the chamber 7 through a non return valve 9. The airway described occurs when the emergency brake has been activated.

The flow of air in the chamber 7 continues until the end of stroke of piston 10, in other words, the non-operating condition. The unit B also includes a channel 2e which connects together a small chamber 14a and the chamber 7 for the flow of air to the said chamber and a channel 2f which starts from the chamber 7 and is designed to release the air from the said chamber once the device has been reset after the emergency brake has been activated.

In particular, the non return valve 4 mentioned previously is designed to always keep the pressure in the tank 2 while the valves 80 and 9 are designed to allow a more rational use of the air necessary for automatically resetting the device and avoid inconvenient returns of air.

The unit B comprises a resetting handle 11 made up of a handgrip 11a and a shank l ib. In particular, the handgrip 1 Ia of an essentially well known type is envisaged for resetting the emergency brake.

The shank l ib has a cylindrical configuration with a pair of notches l ie and Hd which are symmetrical to the axis of the shank, a first projection 1 Ie on the side of notch 1 Id, a groove 1 If and a second projection 1 Ig positioned one after the other on the side of notch l ie.

More in detail, notch l ie does not have any function in non-operating condition while in operating condition of the unit B, that is when the activating handle has been pulled, it connects the first unit A through channels 3 a, 3 b and 3 c and a channel 3f which is connected to channel 3c and ends at the notch l ie releasing into the atmosphere some of the air present in the general conduit.

The outflow of air occurs through channel 3f and also through a calibrated hole 12 positioned next to channel 3f.

Furthermore, the notch Hd does not have any function when the device is in operating condition while in non-operating condition, that is once the handle has been reset to the original position, it favours the discharge of air from the chamber 7 into the atmosphere through a hole 7a which is connected to channel 2f and a discharge channel 2g. Furthermore, when the device is not used notch 1 Id favours the outflow of air caused by small losses from the chamber 7 through the channel 2f into the atmosphere. Furthermore on shank l ib there is a rod 13 whose first section with the end 13a is connected to the shank and the other end 13b to a small piston 14 and the second section is connected to the small piston 14 and the small piston 6.

In addition, the shank l ib is equipped with an articulated joint 15 designed to reset the handgrip 1 Ia of the handle in the non-operating position when the resetting means 16 are activated.

As previously mentioned, the said unit B foresees a main piston 10 which comprises a central shank 10a with, at a first end, a T-shaped element 10b envisaged to run inside the chamber 7 from a resting position, in which the wings of the T are in contact with the internal wall 7b of the chamber 7 and compress a spring 71 into a working position in which the wings of the T are in contact with the opposite wall 7c of the chamber also upon action of the spring 71 which facilitates its movement and, at the other end of the shank, a substantially cylindrical element 10c which is envisaged to move inside a chamber 17. In particular, on the cylindrical element 10c, there are a couple of recesses 1Od positioned symmetrically to the shank 10a and on the side of the latter, envisaged to house a couple of units 50 and 51 connecting to a rotating plate 18. Furthermore, on the side of the recess 1Od that houses the unit 50, in the cylindrical element 10c, there is the groove 8 while on the opposite side is foreseen one groove 81, envisaged for the airflow to charge the tanks 2 going from channel 3d towards channel 3e. Finally the cylindrical element 10c features an arrow-shaped element 1Oe with a point envisaged to close an opening 17a present in the chamber 17. More in detail, to close the opening 17a, the arrow-shaped element 1Oe is assisted by a spring 1Of and a bolt 1Og which, duly adjusted, are envisaged to hold together the surface 17d of the chamber and the surface of the arrow-shaped element which has to withstand the pressure from a conduit 3g and maintain the air tightness. According to the device, the chamber 17 is equipped with a discharge hole 17b of the air from the general conduit and present in the chamber 17, after the device has been reset. Furthermore, the chamber 17 features a spring 17c that contributes to push the cylindrical element 10c in operating condition.

In accordance with the present invention, the said unit B comprises a plate 18 that is rotatably constrained on a point 18a of the bearing structure of the device and is envisaged to rotate clockwise upon the command of the handle 11.

In particular the rotary plate 18 features a protrusion 18b envisaged to engage, when the device is non-operational, the second projection 1 Ig and rotate to move the protrusion 18b away from the second projection 1 Ig when the emergency brake is activated. Furthermore, the rotary plate 18 features a couple of levers 30 and 31, the first one positioned between the protrusion 18b and the rotation centre 18a and the second one position symmetrically to the first one in relation to the rotation centre 18a. More in detail, one end 30a of the said first lever 30 features is pivoted on the rotary plate 18 and the other end 30b is engaged on unit 50. Furthermore the said first lever 30 is equipped with a first spring element 300 envisaged to hold the unit 50 in the recess 1Od. Similarly, one end 31a of the said second lever 31 features is pivoted on the rotary plate 18 and the other end 31b is engaged on unit 51. Also the said second lever 31 is equipped with a second spring element 310 envisaged to hold the unit 51 in the corresponding recess 1Od.

In addition, the rotary plate 18 comprises a couple of small arms 40 and 41 on which the springs 400 and 410 are respectively connected. In detail, the spring 400 is connected to one end of the said first small arm 40 and is envisaged to hold the small arm against a retainer 40b. Similarly, the spring 410 is connected to one end of the said second small arm 41 and is envisaged to hold the small arm against a retainer 41b. The free end of the small arm 41 is designed to enter in contact with an end of a small lever 43 which is held by a spring 43a. The small lever 43 features a small protrusion 43b. Similarly also the free end of the small arm 40 is designed to enter in contact with an end of a small lever 44 which is held by a spring 44a. In addition to the above, the opposite end of the small lever 44 features an enlargement 44b which ends with a small pin 44c. In particular, the small protrusion 43b on the small lever 43 is envisaged to enter in contact with the enlargement 44b holding back the lever itself so that the small pin 44c does not enter into the notch Hf. When the emergency brake is activated, the rotary plate 18 rotates, the second protrusion Hg is released from the protrusion 18b that holds it and when the shank 1 Ib is lowered, the small pin 44c enters into the notch 1 If, thus blocking any other movement of the shank.

In addition to the above, the unit B comprises monitoring means 60 envisaged to signal, at the moment the train is composed, if one or more handles have been pulled and the device is in operating condition. The monitoring means 60 comprise the chamber 5 which is connected to the channel 2a and on one side is connected to the channel 3a by means of a first union 68 and with the channels 3b and 3c by means of a second union 69, and on the other side, symmetrically to the axis of the chamber, is connected respectively to a channel 3h and a channel 3g. The chamber 5 features a piston 61 which constitutes a central rod 61 wherein a first end thereof has an enlargement 61b which touches the internal walls of the chamber and which, when the device is non-operational, moves leaving the passageways with the first union 68 open and symmetrically with the channel 3h, while when the device is in operating condition, the opposite occurs that is to say that the passageway with the channel 2a is opened and the passageways with the first union 68 and the channel 3h are closed. Furthermore, the piston 61 features on the other end of the rod a second enlargement 61c which touches the internal walls of the chamber and which, when the unit B is non- operational, moves closing the airway to the second union 69 open and the channel 3g, while when the unit is in operating condition the opposite occurs that is to say that the airways 69 and 3g are opened. Finally between the other end 5b of the chamber and the free end of the second enlargement 61c there is a spring 63 envisaged to hold the first enlargement 61b in contact with the upper end of the chamber when the device is not operational.

Furthermore the said unit B also comprises a stabilising element 70 envisaged to hold the second projection Hg according to a vertical axis. The stabilising element 70 is engaged with the shank 1 Ib on the articulated joint 15 and is rotatably engaged with the structure of the device in point 70a which presents the same horizontal axis of the articulated joint 15 in non-operating condition.

Resetting means 16 are connected to the stabilising element 70 and they comprise a plate 16a that features a slot 16b for a key. The plate 16a is positioned with one side resting on a retainer 16c and the other held by a spring 16d. To manually reset the unit B, the operator has to insert the key in the slot 16b and turn it clockwise to turn the plate 16a overcoming the resistance of the spring 16d so that the stabilising element 70 can rotate and the small pin 44c can come out of the notch 1 If and the shank 1 Ib can move up and return to the non-operating position.

According to the present invention, the unit B features a disk 50, which acts as piston as detailed in figure 3 and is located in the shank l ib just above the handgrip 11a of the resetting handle 11. The disk 50 features a calibrated slit 50a designed to link up the upper part and the lower part of a chamber 51. The lower part of the chamber 51 is fed, via a calibrated hole 52a, by a conduit 52

More in detail the conduit 52 is connected to the channel 3f. A conduit 53 is housed in the lower part of the chamber 51 and envisaged to supply the third units C, i.e. the emergency brake activating handles present in the different compartments.

The said calibrated hole 52a features slightly larger dimensions than those of the calibrated slit 50a so that the pressure is slightly greater in the lower part of the chamber

51 when there are drops in pressure in the general conduit (for example: in normal braking conditions).

Otherwise, in the event of greater pressure conditions in the upper part of the chamber 51 than in the lower part, there could be an inopportune lowering of the disk 50, with the consequent triggering and intervention of the unit B.

Furthermore, the flow rate of the conduit 53 will be opportunely greater than that of the said calibrated slit 50a.

When the emergency brake is activated by means of the said unit C, air flows out of the calibrated slit 50a and there is a sudden drop in pressure in the lower part of the chamber 51. The force exercised by the pressure on the disc 50, created by the air present in the upper part of the chamber 51, will lower the sic 50 and trigger the emergency brake.

According to the present invention, the device comprises the activating unit C. This unit is installed in the carriages and pilot carriage for remote control trains, obviously in symbiosis with the units B and A as shown in figure 1.

The structure is simple and comprises a conduit 90 which branches out from the conduit

53 and, at the other end, enters a first chamber 91 divided from a second chamber 92 by a second arrow-shaped element 93 which, as shown in figure 4, is endowed with a hole 94 which links up with a discharge hole 95 located on a side wall of the second chamber 92.

The hole 94 is envisaged to guarantee that overpressure does not occur in the second chamber 92 due to draughts from the first chamber 91 in resting conditions.

In fact, any passage of air could inopportunely activate the handle. The arrow-shaped element 93 is equipped, in the lower part, opposite the arrow, with the handgrip 98 of the emergency brake activating handle.

When the handgrip of the handle it is pulled downwards air is suddenly discharged and released into the atmosphere through discharge hole 95.

The discharged air comes from the conduit 53 after having passed through the conduit 90 to reach the first chamber 91 and passes through the second chamber 92 following the downward movement of the arrow-shaped element which opened the passageway between the first chamber 91 and the second chamber 92. hi addition to what has been illustrated above, the unit C also comprises a third chamber

96 which corresponds with a sector of the chamber 92, inside which, as shown in figure 4, the arrow-shaped element 93 runs, which is equipped with an opportunely calibrated spring 97 whose function is to maintain the arrow-shaped element in position so that the passageway between the first and second chamber is closed. Finally, the said third chamber 96 is endowed with a hole 96a envisaged to release the air which could accumulate in the chamber 96 due to draughts between the second chamber

92 and the third chamber 96.

Overpressure should not occur in the chamber 96 as the air which would cause such overpressure would come from the chamber 92 which is endowed with the discharge hole

94.

According to the present invention, the device features a plurality of self-regulating valves

500 located, respectively, in the front driver's cabin and the rear driver's cabin of the locomotive, as shown in figure 5A, and one in the pilot carriage as shown in figure 5B.

Each self-regulating valve is envisaged to regulate the pressure at 5.8 bar in the main conduit to cut off the units B and C, and the regulation is handled by the driver, while the regulation of the 5.8 bar is automatic as it depends on the construction features of the valve.

Always according to the present invention, the device concerned comprises a flow regulator 600, shown in figures 5A and 5B, which creates and removes an airway between a main tank 201 and a self-regulating valve 500 in the locomotive in both the front driving cabin and the rear one, while in the pilot carriage it creates and removes the airway between the main conduit 200 and the self-regulating valve 500 as shown in figure 5B.

Furthermore, as shown in figure 5 A, the device comprises a brake tank 102 which, on the locomotive, is supplied via a one-way valve 110 by the main tank 201 and then supplies, in its turn, the general conduit 100 via a brake isolating valve 120 and a brake control valve 101 in both the front and rear driver's cabins.

The pilot carriage, shown in figure 5B, features a second brake tank 104, which is supplied by the main conduit 200 via a second one-way valve 111 and then supplies, in its turn, the general conduit 100 via a second brake isolating valve 121 and the brake control valve 101. In particular, the one-way valve 111 is of a well known type and is envisaged to allow the air to always flow in one direction and never in the opposite one.

Finally, as mentioned, the device features two valves R and Rl which are located upstream of the first unit A and are mutually coaxial and their normal position is open as shown in figure 1. In the closed position, the function they perform, should the need arise, is to cut off the entire system, including units A, B and C.

Before providing a detailed description of the operation of the device, it is necessary to describe how a brake on a train works.

In order for the actual device to operate, the entire braking system must be filled with compressed air beforehand so it can operate when the emergency brake is activated.

The entire braking system is filled with air through the main conduit 200 and the general conduit 100.

More in detail, the main conduit is supplied from the main tank 201 of the locomotive through conduit 220 and in turn the main conduit partially supplies an auxiliary tank 203 through a valve 221 as shown in figure 5 A.

Furthermore, two conduits 226 and 227 branch out from the main tank 201 and end in corresponding flow regulators 600, respectively in the front and rear driver's cabins, which when open supply the self-regulating valves 500 through conduits 226a and 227a.

As shown in figure 5B also in the pilot carriage the main conduit 200 supplies the auxiliary tank 203 through a valve 221. The compressed air goes from the main conduit, through a first joint and a conduit 230 to a flow regulator 600 which when open supplies the conduit 231 reaching a self-regulating valve 500. Furthermore, a second joint leading off the main conduit leads to a conduit 232 and to the second brake tank 104 with the interposed one-way valve 111. A conduit 223 goes from the tank 104 to the second brake isolating valve 121. Finally, as shown in figure 5C, in the carriage, the main conduit supplies an auxiliary tank 203 through a valve 221 and the air will arrive to valve Rl through conduit 225 and in turn to the unit A. What is stated for one carriage is valid for all the carriages of a train. Furthermore, the general conduit 100 of the locomotive is charged with air from the main tank 201 whose maximum pressure can reach about 10 bar. Air passes through the oneway valve 110 and fills the brake tank 102 from which two conduits 228 and 229 branch off and arrive respectively in the in the front and rear driver's cabins to a brake isolating valve 120 and through two other conduits 228a and 229a to the corresponding brake control valve 101 in both the front and rear driver's cabins. The brake control valve 101 has the function of adjusting the pressure of the general conduit to 5 bar and of braking and releasing the brakes when necessary, therefore, from this point onwards, both the general conduit 100 and the units A, B and C which are connected to it have a pressure of 5 bar.

Finally, as shown in figure 5 A, a conduit 240 and 241 branches off from each brake control valve 101 in the front and rear driver's cabins respectively and is connected to the general conduit which reaches the last carriage.

According to the present invention, from the general conduit 100, a conduit 250 branches off to the locomotive, a conduit 260 to the pilot carriage and a conduit 270 to the carriages and each conduit 250, 260 and 270 reaches a corresponding brake distributor 301. The distributor 301 once charged, manages the braking or release of the brakes of the train through drops in pressure or by rebalancing the pressure to 5 bar.

In detail, the driver brakes or releases the brakes of the train through the brake control valve 101. In addition to the above, a conduit 280 branches off from the general conduit 100 to reach the unit A in the pilot carriage and similarly a conduit 280 branches off to the unit A in the carriage.

As previously mentioned, the air passes from unit A to unit B and then to unit C. From the general conduit 100, the air passes through the valve R to the conduit 20 and then into chamber 21 of unit A. The air then goes into conduit 22 and reaches the air filter F and the conduit 3f.

From the conduit 3f, the air is supplied to conduits branching off unit B as explained later. The air continues along the conduit 3f and reaches the calibrated hole 52a and fills, always at 5 bar, the lower and upper part of the chamber 51 and then continues through conduit 53 until it reaches a branch the supplies the conduit 90 and then the chamber 91 of the unit C. To fill the unit B with air, the air passes from channel 22 and filter F to the channel 3 a where part of the flow of air deviates into the first union 68 as the piston 62 in non- operating condition and the other part of the air continues along channel 3b. As previously mentioned, the brake operation is controlled by the brake control valve 101 in the locomotive which, by international standards, manages and controls the general conduit 100. The value of the compressed air to control the brake of a train is set at 5 bar, therefore to brake the train, the pressure must be lowered below 5 bar and to release the brake or move the train, the pressure in the general conduit must be reset at 5 bar. In particular, the regulating valve 500 has the function of cutting off all the units B and C in the train once the emergency brake has been activated. It is necessary to cut off all the units B and C so that if the emergency brake is pulled again while the train is still in the tunnel it does not stop again.

The units B and C are cut off by the self-regulating valve 500 and by increasing the air pressure to 5.8 bar in all the conduits, the main tank 201 and the main conduit 200. The units A interact with the main conduit 200 and below 6 bar they inhibit the airway that supplies the units B and C therefore even if the emergency brake is activated again it would not have any effect. In these conditions the entire compressed air system, main tank and main conduit are at 5.8 bar, a value that always guarantees the release of the brake. To be prudent, the brake tank 102 is foreseen in the locomotive and the second tank 104 in the pilot carriage, whose capacity is calculated to guarantee the release of the brake taking into account the maximum composition of a passenger train. Obviously all this is obtained by placing a one-way valve 110 between the main tank 201 and the brake tank 102 in the locomotive and the same one-way valve 111 between the conduit 232 and the tank 104 in the pilot carriage as shown in figure 5B. For logistic reasons the self-regulating valve 500 will have an air discharge capacity greater than the capacity of the air production equipment (compressors 700) to produce air.

To achieve this objective, the pressure in the main tank and main conduit must be brought below 6 bar to inhibit the supply of air to units B and C but never below 5.8 bar to guarantee the release of the brake. What has been described with reference to the locomotive is also valid for the pilot carriage. The pilot carriage is also obviously equipped with units A, B and C.

As regards the carriages (figure 5C), the equipment envisaged by the device comprises one unit B and one unit A and a number of units C equal to the number of emergency brake activation points.

When the entire braking system of the train has been filled with air, in case of need, the activation of the emergency brake will stop the train. The operation of the emergency brake envisages the activation of an activating handle 98 by a passenger through unit C by pulling the handle 98 downwards. This movement links up the chamber 91 with the chamber 92 which is endowed with the discharge hole 95. The air discharge causes a sudden drop in pressure, through conduit 90, into conduit 53 and in the lower part of the chamber 51 of unit B.

The almost immediate drop in pressure in the lower part of the chamber 51 causes the force exercised on the disk 50 by the air present in the upper part of the chamber to lower the shank l ib activating the emergency brake of unit B.

The activation of the unit B causes a strong discharge of air from the general conduit and consequently the rapid braking of the train.

More in detail, the intervention of the unit B moves the shank l ib from non operating condition to operating condition. The movement of shank l ib ends when the first projection l ie enters in contact with a retainer 19. Once the unit B has been activated, the air in the channel 3f is released into the atmosphere through the notch l ie and the calibrated hole 12 that has the function of signalling the activation of the emergency brake with a whistle.

Furthermore, the movement of the shank l ib moves the notch Hd removing the possibility of the air present in the chamber 7 being discharged through the channels 2f and 2g into the atmosphere. Furthermore, the movement of the shank moves the rod 13 which moves the small pistons 14 and 6 creating the airway from the channel 3h to the small chamber 14 a and to the channel 2e towards the chamber 7 and the airway from the channel 2c to the small chamber 6a and the channel 2d always towards the chamber 7.

In addition, the movement of the shank 1 Ib entails the movement of the second projection

Hg in the same direction and the latter moves the protrusion 18b, thus rotating the rotary plate 18.

In this situation the second projection 1 Ig remains in contact with the protrusion 18b until the rotation of the plate 18 separates them. During the rotation, the small arm 41 rotates the small lever 43, overcoming the resistance of spring 43a, and moves the small protrusion 43 b from the enlargement 44b on the small lever 44 which will be free to move towards the shank 1 Ib thanks to the action of spring 44a. This movement will place the small pin 44c in the groove Hf, thus blocking any movement of the resetting handle.

The rotation of the rotary plate 18 entails the movement of the levers 30 and 31 (the former downwards and the latter in the opposite direction) which will overcome the resistance of the respective springs 300 and 310 provoking the exit of the corresponding units 50 and 51 from their seats (recesses 1Od) leaving the main piston free to move controlled by spring 71 and by the air that enters from the channel 3g and pushes on the arrow-shaped element 1Oe.

During the movement of the main piston 10, the piston 61 allows the flow of a considerable amount of air from the general conduit 100 through filter F, the channels 3 a and 3b, the second union 69 and the channel 3g to the opening 17a which is then released into the atmosphere through the discharge hole 17b.

The release of air from the discharge hole 17b lowers the pressure in the general conduit and causes the train to brake. The movement of the main piston 10 also entails the movement of the groove 81 and the closing of the airway to the tank 2 of the channel 3e as the air of the channel 3d stops against the cylindrical element 10c. In addition, the movement of the main piston 10 moves groove 8 creating an airway from the tank 2 along the channel 2b through the hole 8a towards the channel 8c and continues along the channel

8d and reaches the chamber 7 through the non return valve 80.

At this point, the automatic resetting of the emergency brake starts. In fact, as previously described, the air accumulated in tank 2 through the channel 2b, the groove 8, the channel

8c and the channel 8d starts to reach the chamber 7.

The input of air in the chamber 7 will start to move the main piston 10 towards the wall 7b of the chamber and this movement will continue until the groove 8 moves and closes the airway between the channel 2b and the channel 8c closing the calibrated hole 8a. While the calibrated hole 8a closes, the air has the possibility of reaching the chamber 7 through the channel 2d which is linked with the tank 2 by means of the channel 2c and the small chamber 6a as the small piston 6 does not hinder said passage in order to allow the main piston 10 to complete its movement towards the wall 7b.

When the main piston 10 ends its movement, the arrow-shaped element 1Oe closes the opening 17a removing the possibility for the air to enter the chamber 17 and be discharged from the discharge hole 17b, and in addition, it allows the units 50 and 51 to return into their seats, the couple of recesses 1Od, triggered by the corresponding springs 300 and 310 and consequently the levers 30 and 31 will make the rotary plate 18 rotate anticlockwise to its original position in non-operating condition.

While the rotary plate returns to its original position, the small arm 40 moves the small lever 44 consequently moving the small pin 44c backwards so that it comes out of the notch 1 If on the shank l ib and while the small pin 44c moves, the small protrusion 43b on the small lever 43 is triggered by the spring 43a and engages the enlargement 44b, thus stopping the small pin from returning into the notch.

Once the automatic resetting described above is complete, the air is restored in the general conduit and in the tank 2 with the passage of air from the general conduit through the channels 3a, 3b, 3c, 3d, groove 8 and channel 3e. During the automatic resetting there is a controlled airway from tank 2 to chamber 7 which is cut off at the right moment with the closure of the hole 8a.

As previously described, at the same time as the said braking takes place, the unit B starts resetting general conduit in the time established.

In these conditions, the train can move in order to move away from a dangerous situation in a tunnel or elsewhere. Now the last thing to do is to manually reset the device and this must be carried out by railway staff.

At this point to return the device completely to the non-operating condition, a person has to insert a special key in the slot 16b of the resetting means 16 and turn it clockwise to turn the plate 16a clockwise overcoming the resistance of the spring 16d. In this way stabilising element 70 can rotate and the shank l ib can move up turning the part of the shank 1 Ib so that the second projection 1 Ig goes over the protrusion 18b and returns to the non-operating position.

Following the upward movement of the shank, the small pistons 14 and 6 will close respectively the channels 2d and 2e while the air present will be discharged into the atmosphere through hole 7a from the chamber 7 passing through the channel 2f, notch 1 Id and the channel 2g and finally the channel 3f and the airway will be closed by the shank, thus interrupting the sound signal.

When the train starts to move again, another passenger may pull the emergency brake again and if this should happen in a tunnel it would cause serious consequences as mentioned previously. For this reason, it is necessary to cut off all the other units B and C of the emergency brake after it has been activated until the train is out of the tunnel. This is possible thanks to the addition of the unit A, flow regulators 600 and self-regulating valves 500.

Whether the train is driven from the front cabin of the locomotive or the rear cabin or the driver's cabin in the pilot carriage the handle M is in position A (open) so it is the brake isolating valve 120 that supplies the brake control valve 101. Since the brake insulating valve 120 is coaxial with the flow regulator 600, the latter will also be open establishing a connection between the main tank 201, conduit 226 or 227 and flow regulator 600, conduit 226a or 227a and self-regulating valve 500. At the right moment the latter will be activated by the driver and this will discharge air from the main tank and the main conduit for the whole length of the train until the value of 5.8 bar is reached. This value (5.8 bar) will trigger all the units A as they are calibrated at 6 bar, thus inhibiting the airway from the conduit 20 to the conduit 22.

In this condition, even if the emergency brake is activated it will not have any effect on the general conduit and consequently the train will not brake.

If the emergency brake be activated in the conditions described above, it will not cause any problem as the unit B involved will reset itself without having any effect on the general conduit, only the handle 98 of the unit C concerned will remain pulled and this will be signalled by the whistle from the calibrated hole 12 through which the whistling air flows out.

Once the self-regulating valve 500, which automatically keeps the pressure at 5.8 bar, has been activated the possibility to release the brake of the train will always be guaranteed. In fact when the self-regulating valve 500 is activated, the air used for the first release of the brakes after the emergency brake has been activated is the air from the brake tank 102 downstream of the one-way valve 110.

When the pressure of the brake tank 102 will be stabilised at 5.8 bar, the main tank 201, through the one-way valve 110 and brake tank 102, will supply the general conduit 100.

The device illustrated so far is completely mechanical or pneumomechanical.

In the above description, in order to cut off all the emergency brake units in a train, the driver used the self-regulating valve 500 to bring the pressure in the main conduit to 5.8 bar. It cannot be excluded that in particularly long trains the rear carriages, those closest to the compressors 700 that produce air, the pressure could be higher than 6 bar. To avoid this situation a variant of the previous device is foreseen which includes an auxiliary control system. The variant of the device previously described envisages a self-regulating valve 500 only in the drive locomotive, that is the locomotive at the front of the train when it is pulled or the locomotive at the rear of the train when it is pushed.

This variant stems from the presence of two different train compositions. The first one is: remote control trains guided by the pilot carriage and driven by the locomotive at the rear of the train and the second one is: trains with two locomotives, one at the front and one at the rear, where the locomotive at the front controls the train and the one at the rear of the train drives the train, in other words, as in the first case, pushes the train. According to the present invention, the auxiliary control system comprises an electric cable which runs along the entire length of the train and serves to electrically control the self-regulating valves 800.

More in detail for the first type of train composition described above, the auxiliary control system, as shown in figure 6A, is composed of an electric power supply 801 with a thermal magnetic overload switch 802 for circuit protection, cables 810 and 820 which extend to the front and rear ends of the locomotive and then continue, via electric couplers, to the rear end of the train (in this case to the pilot carriage). In particular, the cables 810 and 820 will be double to have the possibility of controlling the self-regulating valves 500. The system also comprises two second self-regulating valves 800 and two solenoid valves 850 for control of the self-regulating valves 800, a discharge hole 860 which releases air from the main tank to obtain a value of 5.8 bar.

The control system in the pilot carriage, shown in figure 6B, features the cables 810 and 820 that come from the locomotive, two of which are delivery cables and two of which are return cables, which will power an electric control 870 which is envisaged to operate in positions A and B in order to have two intervention possibilities. The system also features two units 871 whose continuity depends on the pilot carriage control console being enabled, electric control is therefore active when the units are active.

Finally, the control system in the carriage, shown in figure 6C, only envisages the presence of through cables 810 and 820, without the presence of other elements.

The operation of the system described foresees that the current, starting from the batteries

801, reaches the thermal magnetic overload switch 802 for circuit protection. Through the cables 810 and 820, front or rear head of the locomotive (figure 6A), passing through the train carriages, it reaches the units 871 on the pilot carriage control console and then the electric control 870.

The circuit will continue through the return cables up to the locomotive where one of the two solenoid valves 850 will be powered and in turn they will start one of the two second self-regulating valves 800 taking the system to a pressure of 5.8 bar when required.

In the second case foreseen, that is to say a train with a train with two locomotives, one at the front and one at the rear, the control system envisages that the front locomotive, shown in figure 7B and the rear locomotive, shown in figure 7A, have electric power supplies

801, derived from batteries, with a thermal magnetic overload switch 802 to protect the circuit which controls two contacts 880 which will give continuity when the pantograph unit in the rear locomotive is raised and a second contact 881.

The control system also comprises a brake control valve 101 which controls the brake along the entire length of the train, an isolating valve 120 for cutting off the brake control valve 101 and which is coaxial with a flow regulator 600 whose coaxiality permits the air to flow solely with the isolating valve 120 open. Also in this case the system envisages solenoid valves 850 for controlling the second self-regulating valves 800 which maintain a value of 5.8 bar in the main tank 201 and in the main conduit 200. The control system features a discharge hole 860 in each second self-regulating valve 800, an electric control 870 which has two intervention positions, A and B, a one-way valve

110 whose task is to make the air flow in one direction only: from the main air tank 201 to the brake tank 102, a solenoid valve 885 located between the self-regulating valve 500 and the flow regulator 600, a manometer 886 for controlling the pressure in the general conduit.

The self-regulating valve 500 in the driver's cabin is controlled by the driver when required and is equipped with an air discharge hole 501.

The system envisages a control handle M for controlling the flow regulator 600 and the isolating valve 120 and a handle M2 for controlling the self-regulating valve 500.

Also this configuration features cables 810 and 820 and cables 830 and 840 for interfacing between the locomotives, which run through the train's carriages.

Finally, the control system in the carriages, shown in figure 7C, only envisages the presence of through cables 810 and 820, which can be coupled between the carriages or between locomotive and carriage without the presence of other elements.

The operation depends on two situations that must be taken into account:

- The train is controlled and driven by the locomotive at the front therefore the raised pantograph is the one of the locomotive at the front of the train. In this case the self- regulating valve 500 used will be the one of the locomotive so the electrical part is not used.

- The train is controlled by the locomotive at the front but it is driven by the locomotive at the rear of the train therefore the raised pantograph is the one of the locomotive at the rear of the train. In this case the self-regulating valve 800 used will be the one of the locomotive at the rear of the train shown in figure 7A. In this situation the electrical part will be used to operate the self-regulating valve as described above. Starting from the batteries in the locomotive at the front, the electrical part reaches a node

N and a second thermal magnetic overload switch 802a. Then it reaches a contact 881 on the raised part of the pantograph on the locomotive at the front and then the solenoid valve

885 and then returns to the batteries. The solenoid valve 885 allows the flow of air between the flow regulator 600 and the self-regulating valve 800, when contact 881 is open, and closes the air flow when contact 881 is closed.

When the pantograph is raised, the contact 881 is open and when the pantograph is lowered the contact 881 is closed. Consequently, with the active locomotive at the rear, the self-regulating valve of that locomotive will have the task of taking the pressure of the main conduit to 5.8 bar.

Furthermore, after node N the electrical part features the thermal magnetic overload switches 802, then the active contacts 880 when the pantograph of the rear locomotive is raised and then the electric control 870.

From the electric control 870, through the cables 810 and 820, passing through the couplers of the intermediate carriages, the electrical part reaches the rear locomotive, and from here, still through the cables 810 and 820 it reaches the control solenoid valves 850 which when necessary will operate the self-regulating valves 800. In this way, the air in the main tank that supplies the main conduit is released through the discharge hole 860 until it reaches 5.8 bar. The same situation is created when the train is controlled and driven by the rear locomotive and the raised pantograph is on the front locomotive which in this case will correspond to the rear of the train. In the carriages there will only be through cables and no electric circuits.

In this way this invention achieves the aims set.

In fact the present device allows the automatically resetting of the emergency brake in trains once a train has stopped or is about to stop so that the train can always move out of a tunnel or move away from a dangerous situation without the possibility of it stopping again after the emergency brake has been activated.

Furthermore the device for automatically resetting the emergency brake provides a device that automatically resets the brakes without any manual intervention so that the train can move again and exit a tunnel when there is a fire on board and the emergency brake has been activated, and furthermore, when an emergency brake is activated all the others are cut off until the train is out of the tunnel or away from a dangerous situation. Advantageously, the device according to the present invention is structurally simpler and consequently it is more economical and can be installed not only in new trains but also in existing ones.

Furthermore, this device drastically reduces, in case of accident and/or fire in a tunnel, the consequences for people and makes it possible to provide prompt and effective emergency operations. In fact, the device is automatically reset so the train can move the distance necessary to allow people to get off in a safe area. hi addition to what has been stated, the device is capable of offering greater flexibility of use and therefore considerable safety for passengers, railway staff and the train. Advantageously, the device is easy to produce, functional and structurally simple. Naturally, numerous modifications and variants can be applied to this invention while still remaining within the scope of the invention as claimed herein.