Device for releasing brakes of a rail vehicle
Patent Information
- Application Number
- AU2025256688
- Authority / Receiving Office
- AU · AU
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-04-17
- Filing Date
- 2025-03-12
- Publication Date
- 2026-10-29
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
Device for releasing brakes of a rail vehicle Technical Field The invention relates to a facility for releasing brakes of a rail vehicle and to a rail vehicle with such a facility. Prior art Rail vehicles are generally fitted with pneumatic brakes, with what are known as direct brakes also being employed in multiple sets, for example underground trains. Direct brakes are those whose braking effect is achieved by increasing the air pressure in an air line or a brake cylinder. By contrast, in indirect brakes the braking effect is achieved by a spring force on a brake pad or a brake caliper, with the air pressure being employed in order to reduce the braking force or to release the brake. The braking force of parking brakes cannot be modulated and they always act according to the principle of indirect brakes. Specific faults can mean a direct service brake or a parking brake cannot be released, i.e. the vehicle is blocked at the current position. With service brakes that act directly, this can be caused, for example, by a defective brake valve and the remedy is to manually relieve the air pressure in the relevant brake cylinder or also in all brake cylinders of a chassis together. To trigger this venting, cutoff cocks are usually provided inside the vehicle or on the chassis itself, and these can often be operated by means of a Bowden cable. In accordance with customer wishes, electrical emergency releases have also been developed, which enable remotely-operated shutting down. Since it must be ensured at all times that an excessive number of brakes of a vehicle or of a multiple set are not shutdown simultaneously, complex safety circuits are required in order to prevent this. A defective parking brake cannot be released by relieving air pressure since falling pressure causes the brake pads to keep applying pressure. According to the prior art, a defective parking brake can be mechanically released, however, with the spring in the parking brake being released from its position and a spring force thus no longer acting on the brake pad. The attachment of the spring is typically released by means of a Bowden cable in this case. The Bowden cable is operated on the chassis itself, and this can be difficult or even impossible in certain situations, such as narrow tunnels, next to live third rails or at a platform. The same set of problems also exists in compressed air-free electrohydraulic brakes in which a hydraulic oil is employed as the force-transmitting fluid instead of air. However, with emergency releases that can be operated electrically, an outage of the electrical power supply of the rail vehicle can prevent a shutdown from being carried out by the crew. The vehicle therefore has to be repaired between stations. Summary of the invention The invention is therefore based on the object of disclosing a facility, which enables the release of brakes of a rail vehicle, in particular of a multiple set, wherein the operator control actions required for this can be executed from the inside of the vehicle. The object is achieved by a facility for releasing brakes of a rail vehicle with the features of claim 1. Advantageous embodiments are the subject matter of the subordinate claims. According to the basic idea of the invention, a facility for releasing brakes of a rail vehicle is described, wherein a first release facility is provided for releasing a service brake and a second release device is provided for releasing a parking brake, and wherein the first release facility can be actuated electrically with two poles via a first release relay and the second release facility can be actuated electrically with two poles, in a parallel with a parking brake venting valve, via a second release relay, wherein the first release relay is connected to a first supply voltage by means of a three-step switch in the second and third steps of the three-step switch and wherein the second release relay is connected to the first supply voltage only in the third step of the three-step switch, and wherein electrical return lines of the first release relay and of the second release relay are connected to a second supply voltage in the second and third steps of the three-step switch. This achieves the advantage of being able to disable a service brake as well as a parking brake of a rail vehicle, with control actions only having to be carried out inside of the vehicle. Manipulations outside of the vehicle, for example operating pneumatic valves, are omitted. A further fundamental advantage of the inventive facility lies in the fact that it functions with the vehicle’s own power supply and an external power supply can also be fed-in in the event of an outage. Inventively, release facilities are provided which bring about the release of a rail vehicle brake. If the service brake is designed as what is known as a direct brake, then it is advantageous to embody the release facility as an electrically actuated pneumatic valve, which is configured to relieve a brake cylinder of compressed air. With a direct brake, the braking force can therefore be cancelled so the vehicle remains ready to start or is ready to start again even with a defective brake valve of the relevant bogie. If the service brake is designed hydraulically or electrically, for example in a vehicle without a compressed air system, then such a brake system also comprises a controller that is assigned to it. In such an embodiment, the first release facility is accordingly embodied as an electronic circuit in a controller of a brake unit. The inventive facility for releasing brakes of a rail vehicle directs a signal, which brings about the release, to this control unit, which then cancels the braking force. Parking brakes are always designed as indirect brakes, they typically have brake pads pressed by a spring force against a friction partner, for example a brake disk, which are taken off the friction partner by means of compressed air. In the event of a defect of the compressed air supply or a component of the compressed air supply, such as a compressed air valve, it may be impossible to release the parking brake. A mechanical emergency release (second release facility) is therefore provided, which cancels the spring force, for which purpose the attachment of the spring is released and thus a spring force no longer acts on the brake pad. This second release facility should thus be designed as an electromechanical facility, which is configured to unload a parking brake cylinder in a compressed air-free manner. This is inventively brought about by means of an electromechanical facility, for example an electric motor or a pull magnet or a linear drive. In a further preliminary development of the invention, a switching facility is provided by means of which the first supply voltage and the second supply voltage can be jointly connected to and disconnected from an electrical power supply again. In this way the power supply of the emergency release relay can be disconnected, whereby a significantly higher level of safety against faulty operation and accidental releasing of brakes is provided. It is essential that this switching facility has two poles, and likewise the actuators of the release relay and the pneumatic valves. This ensures that simple faults and defects, such as a short to ground at any point of the circuit or supplying voltage to any point of the circuit cannot result in undesirable releasing of a brake. A preferred embodiment of the invention provides that the second release relay is fitted with an on-delay timer and the parking brake venting valve is designed so it can be actuated by a parking brake relay, which is connected to the first supply voltage via the three-step switch only in the third step of the three-step switch and wherein the electrical return lines are connected to an electrical return line of the parking brake relay. A delay between actuation of the parking brake relay and the parking brake venting valve is brought about in this way, with the parking brake venting valve switching before the parking brake relay. Compressed air that is potentially still present in a parking brake cylinder is relieved first of all; the parking brake is thus applied and only thereafter is the second release facility operated. This causes the parking brake to first of all be brought into a defined position and only then be released, that is to say the spring that causes the braking effect of the parking brake is released from its position. A further preferred embodiment of the invention provides the option of being able to bring about releasing of the brakes even with an outage of the internal electrical power supply of the affected rail vehicle. A feed connection is provided for this, which comprises contacts that are electrically conductively connected to the first supply voltage and to the second supply voltage and which is embodied to be able to make contact with an external current supply. Such a feed connection allows the supply of electrical power for operation of the release facility, by way of example from an emergency power supply battery of the rail vehicle, from a further vehicle or a portable current supply. The first and the second supply voltages are advantageously conducted through the entire rail vehicle, so the brakes of each axle, chassis or bogey can be fitted with an inventive release facility. With multi-part vehicles, such as multiple sets or underground trains, it is advantageous to provide one switching facility at each vehicle end, that is to say the end cars, so releasing of the brakes can be initiated from any driver’s cab. The first and the second supply voltages are preferably also conducted through the intermediate cars coupled between the end cars, so brakes in these cars can also be fitted with an inventive release facility. Depending on the desired selectivity of the release facility, one three-step switch can be assigned per axle, chassis or bogey or also to an entire car and jointly release the brakes of one of said units. Brief description of the drawings By way of example, in the drawings: Fig. 1 shows a facility for releasing brakes of a rail vehicle. Fig. 2 shows a facility for releasing brakes of a rail vehicle, with time delay. Fig. 3 shows a facility for releasing electronically controlled brakes of a rail vehicle. Statement of the invention Fig. 1 shows, by way of example and schematically, a facility for releasing brakes of a rail vehicle. This facility comprises a first release facility 1 for a service brake. This release facility 1 is designed as an electromagnetic pneumatic valve and is introduced into a pneumatic system of a rail vehicle such that is allows compressed air to escape from a brake cylinder when it is electrically actuated. In order to simplify the representation, the pneumatic system of the exemplary rail vehicle is not shown in Fig. 1. To release a parking brake, a release facility 2 for a parking brake is provided, which is designed as an electromechanical release facility, which is capable of unloading a parking brake cylinder in a compressed air-free manner, that is to say of canceling the braking force in the compressed air-free state of the parking brake cylinder. For this, the release facility 2 is mechanically connected to a holder of a spring in a parking brake cylinder, which when the release facility 2 is electrically actuated, releases this spring from its operating position and unloads it, whereby the braking force exerted by the parking brake cylinder is canceled. The release facility 1 for a service brake is actuated by a first release relay 1 in a two-poled manner, with the release facility 1 being actuated when the first release relay 1 is closed. In the closed state, the first release relay 1 conducts a first supply voltage 6 and a second supply voltage 7 to the first release facility 1. The first release relay 3 is actuated via a three-step switch 5, which has three switching positions. In a first switching position of the three-step switch 5, the normal or rest position of the facility for releasing brakes of a rail vehicle, the first release relay 3 is not energized, that is to say is not actuated, in the second and the third switching positions of the three-step switch 5, the first release relay 3 is actuated and thus conducts the supply voltages 6, 7 to the first release facility 1, which then releases the service brake assigned to it. The second release facility 2 is actuated by a second release relay 2, with the release facility 2 being actuated when the second release relay 4 is closed. In the closed state, the second release relay 4 conducts the first supply voltage 6 and the second supply voltage 7 to the second release facility 2. Electrically parallel to the second release facility 2 is a parking brake venting valve 10, which is configured such that in the actuated state it allows the compressed air in a parking brake cylinder to escape. This part of the compressed air system of the rail vehicle is not represented in Fig. 1 either. The escape of the compressed air from the parking brake cylinder brings about the build-up of the braking force of the parking brake, although the spring causing the braking effect is partially relaxed in the process. The attachment of this spring is therefore released by the second release facility 2 with the lowest possible pre-tensioning force of this spring, the release mechanism is thus exposed to the lowest possible mechanical load, so the drive force, which is to be applied by the second release facility 2, is also reduced. The second release relay 4 is similarly actuated via the three-step switch 5. In a first switching position of the three-step switch 5, the normal or rest position of the facility for releasing brakes of a rail vehicle and in the second switching position, the second release relay 4 is not energized, that is to say not actuated. In the third switching position of the three-step switch 5, the second release relay 4 is actuated and thus conducts the supply voltages 6, 7 to the second release facility 2, which then releases the service brake assigned to it, as well as to the parking brake venting valve 10. Thus with a single control action at the three-step switch 5 the inventive facility allows either a service brake to be deactivated or a service brake together with a parking brake to be deactivated. To increase the operating safety and as protection against instances of false triggering of the release facilities 1, 2, all electrical actuators have two poles. Accordingly both the electrical supply line and the return line are switched, a single fault, for instance the application of external voltage to any component of a circuit, can accordingly not result in an undesirable release of a brake. The shared electrical return line 8 of the release relay 3, 4 is therefore also guided via a further branch of the three-step switch 5, with the electrical return line 8 being connected to the second supply voltage 7 only in the second and third switching steps of the three-pole switch 5. Connected upstream of the facility for releasing brakes of a rail vehicle is a switching facility 9, which is suitably embodied for connecting and disconnecting the supply voltages 6, 7 to / from an electrical power supply 12. Two operating steps are therefore required to release a brake, and this significantly reduces the risk of incorrect operation. The switching facility 9 can be arranged, for example, in a driver’s cab, the facility for releasing brakes, i.e. the three-step switch 5 as well as the release relay 3, 4, can be provided, by way of example, per vehicle or per chassis. The exemplary embodiment shown is therefore fitted with a feed line to further release facilities 14, and forwards the supply voltages 6, 7 to further facilities or to further coupled vehicles and the facility thereof for releasing brakes. This is advantageous, in particular, in types of vehicle that are not decoupled during operation since any electrical lines can be guided through the entire combination of vehicles in this case since electrical couplings in line with standards do not have to be heeded. Fig. 2 shows, by way of example and schematically, a facility for releasing brakes of a rail vehicle with a time delay. A release facility very similar to the exemplary embodiment shown in Fig. 1 is represented, which a time delay between actuation of the parking brake venting valve 10 and actuation of the second release facility 4 when a parking brake is released. For this, a parking brake relay 11 is provided, which is wired in an identical manner to the second release relay 4 shown in Fig. 1 and which is actuated in the third switching step of the three-step switch 5. In the actuated state this parking brake relay 11 energizes the parking brake venting valve 10, so the compressed air in the assigned parking brake cylinder can flow out and the brake parking brake is thus applied. The second release facility 2 is actuated via a second release relay 4.1 with a time delay, which is switched in an electrically parallel manner to the parking brake relay. After actuation of this second release relay 4.1 and the specific time delay of this relay, the second release facility 2 is energized and therefore releases the spring in the parking brake from its position, so the parking brake is released. The duration of the time delay should be such that when it has expired the pneumatic cylinder of the parking brake is vented to the extent that the spring can be released without the risk of damage to the parking brake and with sufficiently low application of force, so the force that can be applied by the second release facility 2 is sufficient to release the spring. The further components of the circuit of this exemplary embodiment are identical to those in the exemplary embodiment represented in Fig.1. Fig. 3 shows, by way of example and schematically, a facility for releasing brakes of a rail vehicle with electronically controlled brakes. A service brake is designed, by way of example, as a hydraulic or electric brake, as is required in vehicles without a compressed air supply. Release due to relieving of compressed air cannot occur, therefore. These hydraulic or electric brakes are fitted with controllers that are assigned to them, which typically have a signal input for releasing the brake. This also relates to pneumatic-free parking brakes. According to this exemplary embodiment, the facility for releasing brakes of rail vehicles is fitted with release facilities 1.1 and 2.1, which are actuated in a manner identical to that in Fig. 1 or 2, but as a control input of a first release facility 1.1 for an electronically controlled service brake and as a control input of a second release facility 2.1 for an electronically controlled parking brake. It is essential to note that any combination of electronically actuated release facilities and electromagnetically actuated 5 release facilities can be provided. A vehicle can thus be fitted with an electronically controlled hydraulic brake together with a conventional compressed air parking brake, likewise with an inventive facility for releasing brakes. The exemplary embodiment shown in Fig. 3 represents a further 10 feature that may be provided in any embodiment of the facility for releasing brakes of a rail vehicle. According to this development, a feed connection is provided via which electrical power can be supplied directly to the lines of the first 6 and second 7 supply voltages. The brakes on a vehicle 15 with a defective electrical power supply 12 can therefore also be released electrically and remotely by the facility represented here. List of reference numerals 1 first release facility for service brake 1.1 first release facility for service brake, electronic 2 second release facility for parking brake 2.1 second release facility for parking brake, electronic 3 first release relay 4 second release relay 4.1 second release relay with time delay 5 three-step switch 6 first supply voltage 7 second supply voltage 8 electrical return lines 9 switching facility 10 parking brake venting valve 11 parking brake relay 12 electrical power supply 13 feed connection 14 supply line for further release facilities
Claims
1. A facility for releasing brakes of a rail vehicle, wherein a first release facility (1) is provided for releasing a service brake and a second release facility (2) is provided for releasing a parking brake, characterized in that the first release facility (1, 1.1) can be actuated electrically with two poles via a first release relay (3) and the second release facility (2, 2.1) can be actuated electrically with two poles, in parallel with a parking brake venting valve (10), via a second release relay (4), wherein the first release relay (3) is connected to a first supply voltage (6) via a three-step switch (5) in the second and third steps of the three-step switch (5) and wherein the second release relay (4) is connected to the first supply voltage (6) only in the third step of the three-step switch (5), and wherein electrical return lines (8) of the first release relay (3) and of the second release relay (4) are connected to a second supply voltage (7) in the second and third steps of the three-step switch (5).
2. The facility for releasing brakes of a rail vehicle as claimed in claim 1, characterized in thata switching facility (9) is provided by means of which the first supply voltage (6) and the second supply voltage (7) can be jointly connected to and disconnected from an electrical power supply.
3. The facility for releasing brakes of a rail vehicle as claimed in claim 1 or 2, characterized in thata second release relay (4.1) is fitted with an on-delay timer and the parking brake venting valve (10) can be actuated by a parking brake relay (11), which is connected to the first supply voltage (6) via the three-step switch (5) only in the third step of the three-step switch (5) and wherein the electrical return lines (8) are connected to an electrical return line of the parking brake relay (11).
4. The facility for releasing brakes of a rail vehicle as claimed in claim 3, characterized in that the second release facility (2.1) is designed as an electromechanical facility, which is configured to unload a parking brake cylinder in a compressed air-free manner.
5. The facility for releasing brakes of a rail vehicle as claimed in claim 3, characterized in thatthe second release facility (2.1) is designed as an electronic facility, which is configured to unload a parking brake cylinder in a compressed air-free manner.
6. The facility for releasing brakes of a rail vehicle as claimed in one of claims 1 to 5, characterized in thatthe first release facility (1) is designed as an electrically actuated pneumatic valve, which is configured to relieve the brake cylinder of compressed air.
7. The facility for releasing brakes of a rail vehicle as claimed in one of claims 1 to 5, characterized in thatthe first release facility (1.1) is embodied as an electronic circuit in a controller or a brake unit.
8. The facility for releasing brakes of a rail vehicle as claimed in one of claims 1 to 7,characterized in thata feed connection (13) is provided, which is electrically conductively connected to the first supply voltage (6) and the second supply voltage (7) and which is embodied so it can make contact with an external power supply.
9. A rail vehicle, comprising at least one facility for releasing brakes of a rail vehicle as claimed in one of claims 1 to 8.
10. The rail vehicle as claimed in claim 9, characterized in thatthe rail vehicle is constructed as a multiple unit with two end cars and at least one intermediate car coupled between the end cars, wherein a facility for releasing a service brake and a parking brake is arranged in each end car, wherein the first supply voltage (6) and the second supply voltage (7) of the two end cars are connected together and is conducted through the intermediate car.
11. The vehicle as claimed in claim 10, characterized in thatat least one facility for releasing a service brake and aparking brake is arranged in each of the intermediate cars.