Resumen de Consideraciones sobre los problemas actuales del frenado de vehículos ferroviarios
One of the main characteristics in the present railways development is the rise in speed of the passenger trains that cause large and difficult problems, especially in braking.
It is possible to classify the brakes in systems where the kinetic energy is destroyed by solid rub, and the so-called dynamic brakes. These last ones seems more appropriate than the firsts to destroy the kinetic energy at very high speeds, but his effectiveness is weak at low speed, and it is necessary to complete with a rub brake.
Among the dynamic brakes, the rheostatic brake is certainly the most suitable, but only applicable to motive axles. It is possible to think about an hydraulic solution, like in the BR, with an operational application in the APT branches. Also it is possible to use the Foucault's current when the rate of motive axles is near to ½ and enough electric energy is available. In this way the SNCF is getting ready, applying over the TGV prototype a rotatory brake derivative from the used in this big trucks. The rotary brake works correctly, but his effort is insufficient, this is the reason why it should not be used in next models.
The stake brakes are effectives, but have the inconvenient of heating in rails and technical fittings.
Among the rub brakes, only the disc one seems the most suitable, though there are another possibility in the SENF brake. This one has been proved with success in the Vichy's Text Center, but are necessary texts on line to give an opinion.
The disc brake allow to get high speeds, from 200 to 300 Km/h. The disc's mechanical arrangement in two parts must observe certain conditions. Ventilation system must be effective.
Another research way may be open up, foreseeing the use of synthetic pastilles that make possible a rise in the work limit temperature.
