Howard Simpson - The Simpson Gearset

The Simpson Gearset

Simpson's preferred gearset was for a three-speed automatic transmission using two identical planetary gearsets in series, linked by a common sun gear. The use of largely identical parts for the front and rear gearset made the transmission substantially cheaper to manufacture by reducing tooling costs. This three-speed gearing arrangement, patented in 1950, is commonly known as the "Simpson Gearset," although it is only one of numerous arrangements Simpson successfully patented during his life.

In the early 1950s Simpson attempted to sell his patent to major American automakers in Detroit, but was greeted with skepticism, despite his experience and positive reputation. Ford Motor Company licensed his three-speed gearset in 1953, although they did not put it into production. In 1955 Chrysler Corporation licensed the same gearset for use in their new three-speed Torqueflite automatic, which went into production in mid-1956. General Motors was reluctant to adopt this gearset, but eventually relented and licensed it for the Turbo Hydramatic, which entered production for the 1964 model year. Ford similarly introduced reengineered Cruise-O-Matic transmissions (C3, C4, and C6) using the gearset they had already licensed. The Simpson-geared Cruise-O-Matics were introduced in the 1964 and 1965 model years. Germany's Daimler-Benz licensed the gearset as well, although it did not enter production until the early 1970s, as the Mercedes-Benz three-speed automatic.