A buffer stop
(US) is a device to prevent railway vehicles
from going past the end of a physical section of track
The design of the buffer stop is dependent in part upon the kind of couplings that the railway uses, since the coupling gear
is the first part of the vehicle that the buffer stop touches. The term "buffer stop" is itself of British origin, railways in Great Britain
principally using buffer
-and-screw couplings between vehicles.
Several different designs have been developed for buffer stops, depending on the coupling system in use.
- Buffer stops with anticlimbers
- Buffer stops for a knuckle coupler (centrally positioned between the two rails)
- Buffer stops with traditional "buffers" on either side
- Hydraulic buffer stops
- Friction buffer stops (bolted down to the rail)
In rapid transit applications, hitting the bumper block is usually a very bad thing, because of the number of passengers involved and the confined space of the tunnel. Rapid transit systems have developed buffer stops that have built-in corrugated anticlimbers
that engage and interlock with the anticlimbers on the car's end sill, which prevents telescoping
of the cars during impact. These bumper blocks can be identified by their distinctive 'fins' appearance.
If there is extra room behind the bumper block, there is usually a sand or ballast drag that is designed to further retard a runaway train. One such accident occurred when a Northern Line train powered... Read More