Emergency brake
An emergency brake is a technical device for triggering immediate braking in order to avert danger. For example, railroad vehicles that are used to transport people or elevator systems are equipped with emergency braking devices that can be operated by passengers. Applying the emergency brake without a valid reason is usually a criminal offense, as the abrupt braking of the vehicle can endanger other people and other road users and disrupt operation. Most emergency brake handles are provided with a locking mechanism that only allows them to be restarted after unlocking or acknowledgment.
Emergency brake on the railroad
The emergency brake fulfills two tasks: On the one hand, in the event of damage that affects the running ability of a wagon, the train should be brought to a stop as quickly as possible. On the other hand, the driver and the train attendants should be made aware of a special emergency situation within the train. It serves both technical and communicative purposes.
Before the introduction of the automatic brake
With the compartment coaches usually used in passenger transport in the 19th century , it was difficult for travelers on a moving train to alert the train staff in an emergency. In Great Britain , a continuous rope was therefore initially attached to the outside of the trains . If it was pulled, a signal sounded on the locomotive and the engine driver could give the whistle signal for the brakemen on the train to apply the brakes . This system was invented by Thomas Elliot Harrison , first installed on the North Eastern Railway , and approved by the State Railway Inspectorate in 1859. In practice, however, it turned out to be insufficiently reliable. Because the cable was on the outside, it was difficult to reach for travelers. The continuous pull rope had to be loosened and reconnected when maneuvering. The former was fixed by relocating the rope inside the car. That happened after 1873, when due to the numerous breakdowns that had also led to serious accidents, the supervisory authority revoked its approval of an external emergency line.
In Germany this cable was called "Rollleine" . This triggered a whistle signal to the brakes on the locomotive. In September 1913, the Kölnische Zeitung reported the following emergency braking:
- “A notorious burglar jumped out of the train while it was being transported from Prüm to Trier. The guard pulled the Rolleine. The criminal was found badly injured and unconscious on the track. "
Emergency brake with compressed air brake
Railway trains are equipped with a compressed air brake with a continuous compressed air brake line. If the brake is released, there is an overpressure of 5 bar in the compressed air brake line ( main air line ) . To initiate braking, the pressure within the main air line is reduced, with regular braking down to 3.5 bar. When the emergency brake is actuated, on the other hand, the continuous main air line is opened locally to the open atmosphere via an emergency brake valve, which means that the air line is gradually ventilated, i.e. the overpressure is completely lost, and the brakes are particularly strong in order to move the train as quickly as possible - faster than with standard braking - to delay.
Actuating devices for initiating emergency braking (so-called emergency brake levers, also known as emergency brake handles) are located in every car of a train, in the case of compartment cars in every compartment of a car. The classic emergency brake valve, also known as the “Ackermann valve” after its inventor, is usually only installed once in each car. It works like a cap on a sheet steel fuel canister and is connected to the emergency brake handles by a sturdy steel wire. A long opening lever allows the main air line pressure to be overcome. In order not to pollute the interior of the car with the escaping compressed air, the emergency brake valve is installed in a special compartment with a connection to the outside air. It is marked with a red colored ring so that the train crew can easily find the installation location, which is different for almost every type of car. In freight wagons with handbrake platforms, as well as locomotives and construction machinery, the emergency brake valves are installed open and can be operated directly. The mechanical emergency brake valve can only be closed again when the main air line is depressurized.
In trains in which it can be determined electronically which of these actuating devices has been actuated, train staff go to the appropriate point and initiate further measures. In trains that do not have such electronic displays, after an emergency brake has been initiated by a passenger, the driver makes a special announcement to the conductor . In this case, the train attendants must first use the switch cabinet or display of each car to check in which car the emergency brake was actuated, then check each individual actuation device in the corresponding car and then initiate further measures.
Emergency brake with electro-pneumatic brake
Newer railcars or multiple units have direct-acting electropneumatic brakes with brake computers, for which the emergency brake is carried out with an electric wire. From the active driver's cab, a feed loop is routed over all coupled train parts to the last unused coupling. The coupling connects the feed loop with the release loop. This is returned to the active driver's cab and evaluated there. All emergency brakes are in the release loop. No signal on the release loop means the emergency brake is active. The activated emergency brake train is displayed to the driver.
Emergency brake override
Trains traveling on longer tunnels or bridge structures must be able to bypass the emergency brake in the area of these tunnels or bridge structures in order to enable the train to leave the tunnel or bridge structures. For this purpose, these trains are equipped with an emergency brake override with which the driver can prevent the emergency brake and the train can leave the tunnel or the bridge structure without stopping. For the emergency stop, stopping points have been prepared behind the structures, at which there are escape routes and entrances for rescue workers.
"Minden 2004" system
On vehicles equipped with this system, the emergency brake handle only has an immediate effect on the vehicle brake in the platform area (a few seconds before to a few seconds after the stop). During the journey, the driver is only informed of the passenger's emergency braking request, who then brakes at his own discretion.
Law
The German Railway Construction and Operating Regulations (EBO) stipulate in Section 23 (3):
- “Vehicles in which people are transported must have easily visible and accessible emergency brake handles that can be used to initiate emergency braking. The emergency braking device may be designed so that an initiated emergency braking can be canceled. In the case of urban rapid transit vehicles , it is permissible that the actuation of an emergency brake handle outside of the platform areas only triggers a display in the driver's cab. "
The misuse of an emergency brake, i.e. an intentional actuation without the intention of averting a danger, is an offense in Germany according to § 145 StGB ( misuse of emergency calls and impairment of accident prevention and emergency aid ). Due to the abrupt stop of transport, there may also be an offense of bodily harm . The costs arising from this (traffic failure, physical injuries) can be charged to the person responsible.
Trivia
One popular canon is the emergency brake.
See also
- Emergency stop : Safety device for interrupting the energy supply to machines
- Emergency brake override : device to (temporarily) cancel the effect of the emergency brake
- Dead man's facility
- Emergency braking
literature
- Lionel Thomas Caswell Rolt : Red for Danger . Edition: London 1978.
Remarks
- ^ For example, the Shipton-on-Cherwell railway accident in 1874.
Individual evidence
- ^ Hans-Heinrich Grauf: The emergency brake concept for new lines . In: The Federal Railroad . tape 64 , no. 8 , August 1988, ISSN 0007-5876 , pp. 709-712 .
- ^ Rolt: Red for Danger , pp. 79f.
- ^ Rolt: Red for Danger , p. 80.
- ↑ Kölnische Zeitung of September 3, 1913, morning edition No. 995, p. 2
- ^ Frank Minde: Lecture "Basics of Railway Brake Technology " . Ed .: Deutsche Bahn AG. July 6, 2007, p. 14 ( uni-hannover.de [PDF]).
- ↑ To Stop the Train. In: Reinhold Brunner's RHYTHM homepage. Retrieved June 7, 2019 : "Canon with movements - from England"