Air brake (road vehicle)

Air brakes are used in trucks, buses, trailers and semi-trailers. George Westinghouse first developed air brakes for use in railway service. A safer air brake was patented by him on March 5, 1872. Originally constructed for use on trains, and still in common use as such, Westinghouse made many alterations to improve his invention, leading to various forms of the automatic brake, thus, its use was expanded to include road vehicles.
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