External brake
The external brake is one of the mechanical braking devices on tenders and tank locomotives to slow down or stop their travel. It also serves as a backup when the vehicle is stationary to prevent it from rolling away unintentionally.
history
The railway engineer and inventor Carl Exter , who lives in Munich, developed a lever brake around 1870. The external brake or Extersche lever brake , named after him , belongs to the category of weight brakes . These are also known as throw brakes or throw lever brakes . The external brake was able to prevail in the tank locomotives. However, it was not used as a car brake because of the fast-acting but poorly controllable braking power.
Around the middle of the 19th century, the train lengths, the train weights and the driving speeds were still very modest. For these reasons, braking the trains using hand brakes was considered sufficient. If the journey was to be slowed down, the stoker's job on the locomotive was to flip the weight lever of the lever brake. The attached cars were often provided with spindle brakes (or other types of hand brakes). The train crew or the brakemen had to operate the car brakes via a whistle signal from the locomotive . Due to the increase in train weights and travel speeds, the demands on the braking systems also increased .
function
If the journey is to be slowed down, the weight lever of the lever brake must be thrown. The brake pads are pressed onto the running surfaces of the wheels via a lever system. The braking effect starts immediately. With appropriate physical effort, the braking effect can be increased. The brake pads are released from the wheel by lifting the weight lever.
If a vehicle is to be secured when stationary, the weight lever can be locked in the lowered position.
With increasing wear of the brake pads, the braking effect decreases. The condition of the blocks must therefore be checked regularly. As far as possible, the rod length can be adjusted or the blocks have to be replaced.
Individual evidence
- ↑ Dr. Freiherr von Roell: Encyclopedia of Railways , 1912–1923, Vol. 3. Berlin, Vienna 1912, p. 16
- ^ Otto Lueger: Lexicon of the entire technology (weight brakes), 1904, Stuttgart and Leipzig Deutsche Verlags-Anstalt. Vol. 2, p. 264
- ↑ Dr. Freiherr von Roell: Encyclopedia of Railways , 1912–1923, Vol. 3. Berlin, Vienna 1912, pp. 16–52