On a
roller coaster train
In rail transport, a train (from Old French , from Latin , "to pull, to draw") is a series of connected vehicles that run along a railway track and transport people or freight. Trains are typically pulled or pushed by locomotives (often ...
, the underfriction, up-lift, or up-stop wheels are a device to keep the train from jumping off the track under intense movement. The design was patented in 1919 by
John A. Miller.
References
Roller coaster technology
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