A History of the Automatic Transmission

The automatic transmission has a long history. It has come a long way since 1924, when it was first installed in vehicles. Since then, many have seen automobiles with automatic transmissions superior to manual ones. Let’s dive deeper into the history and prominence of the automatic transmission.

What is an automatic transmission?

A closeup of a six-gear automatic transmission displayed at ZF Friedrichshafen headquarters in Germany
A closeup of a six-gear automatic transmission | THOMAS KIENZLE/AFP via Getty Images

An automatic transmission is a transmission with no gears but an electronically controlled system that does the shifting. This system’s torque converter helps redirect engine power from the crankshaft to the wheels.

The engine produces power at different speeds; if you want more torque or power, it needs to increase its speed (rpm). The engine does this by increasing the fuel and air intake into the engine, which makes it work harder and produce more power. This is known as overdrive mode on your car’s dashboard display. Automatics use an electromagnetic clutch assembly to match engine rpm with road speed, so there is no need to shift between gears.

History of the automatic transmission

According to Tech Historian, the automatic transmission was first developed in the early 1900s by Karl Benz, who also invented the modern automobile. However, General Motors Corporation employees Edward A. Deeds and Charles F. Kettering developed the first automatic transmission widely employed in automobiles in 1924. They called their invention the “Clutchless Hydra-Matic” and introduced it in Oldsmobiles for the 1928 model year.

The Kettering-Deeds Hydra-Matic was a two-speed planetary gear set. It featured a direct drive between the engine and output shafts through a fluid coupling. When the driver pressed the accelerator pedal, fluid pressure increased within an oil pump that supplied pressure to the throttle body. It engaged and disengaged clutches on demand inside the transmission during shifting. The system also included a freewheeling device that allowed coasting without using gears.

Why is automatic transmission commercially successful?

The automatic transmission has gained popularity over the years for its convenience. It makes driving easier, helps save fuel, and reduces the risk of accidents due to poor driving skills or terrible weather conditions. Most modern vehicles, including cars, trucks, and motorcycles, have automatics.

Automatic transmissions vary: from the four-speed, five-speed, and six-speed variants, designed according to their power capacities and efficiency levels.

How an automatic transmission differs from a continuously variable transmission (CVT)

J.D. Power defines a continuously variable transmission (CVT) as an automatic transmission that can change gears smoothly without requiring mechanical linkages.

The main difference between an automatic and a CVT is that the automatic transmission has several gears selected by a clutch and shift mechanism, whereas a CVT has no such gears. Instead, the CVT uses two pulleys with rubber belts running between them to provide variable gearing as the vehicle accelerates or decelerates. The belts also allow the engine’s power output to match the vehicle’s speed and load requirements, which would not be possible in an automatic transmission, which relies on mechanical linkages between gears.

This transmission makes it easier for drivers to accelerate from rest without manually shifting gears. It differs from manual transmissions or automatics with multiple gear sets. Instead, they can press the accelerator pedal until they reach their desired speed. CVTs are also commonly used on bicycles because they are simple and lightweight.

Why the manual transmission is dying

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Why Are Manual Transmissions Dying and What Will Kill Them Off Completely?

There are several factors contributing to the demise of manual transmissions. First, the manual transmission has always been a niche market for performance cars and sports sedans, but many of those models are going away altogether. The latest trend in performance cars is all-wheel drive, which makes it harder to sell a manual transmission as they’re generally only available with rear-wheel drive.

Second, manufacturing manual transmissions is more expensive than automatics because they require more parts and labor to build. Automatics are cheaper because they have fewer parts and require less labor. 

Third, automatic transmissions have improved dramatically over the past decade. This is due to the improvements in technology and electronics, whereas manuals haven’t changed much since the 1980s.

The automatic transmission has been a revolutionary invention for the auto industry, making it easier for more people to learn how to drive and making driving a more viable option for everyone. Additionally, automatics solved the power loss issue in car engines, became more prominent and influential, and made driving safer.