Vacuum brakes

In the mid-1860s a type of brake called the vacuum brake was introduced to railway locomotives. A well known variant of this brake is the Automatic Vacuum Brake. The Vacum brake is no longer used as it was replaced by Compressed air brakes.
==How Braking is Achived==
In its simplest form, the automatic vacuum brake consists of a continuous pipe -- the train pipe -- running throughout the length of the train. In normal running a partial vacuum is maintained in the train pipe, and the brakes are released. When air is admitted to the train pipe, the air pressure acts against pistons in cylinders in each vehicle. A vacuum is sustained on the other face of the pistons, so that a net force is applied. A mechanical linkage transmits this force to brake shoes which act by friction on the treads of the wheels.
Category:Terms
Category:Brakes