Freight Car Brake Chronology
1868 Air brake (straight air) invented : Patent date March 5, 1868. Primarily used on passenger trains. Note: straight air is generally considered suitable for trains up to 8-10 cars
1872 Automatic air brake (F triple valve) invented : 1873 introduced. Considered suitable for trains of up to 20 cars
August 1874, Eames receives patent for vacuum brake
Jan 11, 1876, patent 172064 to George Westinghouse for “automatic” air brake valve
1876 Eames vacuum brakes introduced (this will later become New York Air Brake Company)
1886 First Burlington Airbrake Trial : MCB sponsored test of commercial air brake systems. The stated goal was to be able to control a train of 50 cars. The first test showed problems, particularly in emergency application
1887 introduction of H triple valve (first “fast action” triple) in part to address issues identified during the First Burlington Air brake test.
1887 Second Burlington Airbrake trial. Westinghouse H triple valve passes 50 car test
1893, Railway Safety Act
1903, Significant deadline for 1893 Railway Safety Act
1906/07 introduction of K triple valve (80-100 car trains) (invented 1905? Per White)
1909/10 updated Railway safety act… changing rules for grabs and spacing between coupled cars.
1912 – Westinghouse and New York Airbrake cross license technology, the “Treaty of Wilmerding”
1933 AB brake introduced, installation required on new construcktion, deadline for installation on a existing car revised several times
c. 1952 AB mandatory for interchange
Notes:
Many of the valves have a number following the valve (example, K-1, K-2) These numbers indicate the size of the valve and how large a brake cylinder it can support.
Randy Hees