Otis patentIn 1852, Elisha Graves Otis was issued a U.S. patent for a “Railroad-Car Truck and Brake” (No. 8973). Otis is well-known for his invention of the safety elevator in the same year, which used automatic braking devices to arrest the fall of an elevator car if its supporting cable broke. His inventiveness also spanned making a turbine waterwheel (1848), a steam plow (1857), rotary oven (1858) and steam elevator (1861). In his patent for the railroad car brake, he described a way to link rods running the length of each car in a train that activated brakes, and connected with compensating joints to the next car's rod. Thus a single lever could apply all brakes simultaneously. He also described his idea to construct guards enclosing wheels on the trucks, such that if a wheel or axle broke, the car would safely remain on the tracks.« |