Track brake

It consists of brake magnets, pole shoes, a suspension, a power transmission and, in the case of mainline railroads, a track rod.

Three years later, the electromagnetic track brake was introduced in Germany by the Westinghouse Company.

Even the winding numbers of the exciter coils were different in order to be able to regulate the brake force.

Thus, the track brake was also equipped with several shoes in order to be able to adapt to possible unevenness of the rails.

These were track magnets with an attractive force of around 4 kN, which lowered automatically onto the rails when the current was switched on, pressing onto the brake shoes and on the wheels of the cars via a lever rigging.

At that time, it had not yet been recognized that track brakes should work independently of the friction between the rail and the wheel.

In 1908, Mr. Jores took over the Westinghouse representation for track brakes in Germany and played a major role in their continuation.

After World War I, Jores led the production of his own track brakes after the patent rights had expired.

The main feature of the track brake at that time were the rail shoes, which were made of a special rolled section.

At the beginning of 1930, the German Imperial Railways initiated a high-speed rail project that envisaged speeds of up to 160 km/h (99 mph) and was to be of great significance for the track brake.

Following the principle of an electromagnet, it consists of a coil wound around an iron core, which is enclosed by horseshoe-shaped magnets.

This causes an attractive force between the brake magnet with the pole shoes attached to it and the rail.

[8] Magnetic track brakes must also work safely in the event of a contact line failure.

The braking system must therefore be designed in such a way that, in the event of a power failure, a supply from the vehicle's batteries is guaranteed at all times.

In the event of braking, the magnet automatically attracts itself to the rails against the effect of the suspension springs.

Between the two pole shoes, a non-magnetic strip ensures that a magnetic short circuit does not occur.

[17] In the deactivated state, the magnets are de-energized and the brake square is brought into the high position.

The wear of steel pole shoes is low, but they form weldings which have to be knocked off regularly.

Pole shoes made of sinter offer increased brake performance and do not form weldings, but their wear is higher.

In France, cast iron is the standard friction material used for magnetic track brakes.

Heavy rail vehicles in the UK do not typically used magnetic track brakes as they can interfere with signalling systems.