Underfriction
Encyclopedia
Roller coaster
The roller coaster is a popular amusement ride developed for amusement parks and modern theme parks. LaMarcus Adna Thompson patented the first coasters on January 20, 1885...
train
Train (roller coaster)
A roller coaster train or car describes the vehicle which transports passengers around a roller coaster's circuit. More specifically, a roller coaster train is made up of two or more "cars" which are connected by some sort of specialized joint. It is called a "train" because the cars follow one...
, 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 Miller
John Miller (entrepreneur)
John A. Miller was a roller coaster designer and builder. He held over 100 patents, many of which were for roller coaster safety devices , that remain key components of present-day roller coasters...
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