Planetary automatic transmission (AT) or a usual automatic transmission. According to the manufacturer of the transmission ZF, today’s automatic transmission is “a major achievement of innovation”.
The beginning of this type of transmission is considered to be of different estimates at the 1940s when the 4-speed Oldsmobile Hydra-matic was introduced. It is the most sophisticated transmission type that uses different gear mechanisms (planetaries) to achieve different transmissions or gears.
The various cogwheels are held or tied with different clutches. As a rule, these transmissions are equipped with a hydraulic coupling or turbine. It is a transmission capable of transmitting the greatest power from the automatic transmission (read: is the strongest), but also the most massive and at the same time more expensive to produce.
That’s why 6, 7, 8, and 9-speed automatic transmissions are mostly used on powerful cars and more on premium class ones. Previously, transmission manufacturers focused on how to “invent” as many moves as possible in order to achieve fuel savings, while the current level (8- and 9-speed boxes) has led to an optimal reduction in the weight of moving parts, the use of more liquid oils, and the addition of transmission start-stop function as well as hybrid drive (electric motor with generator).
We often heard that “my car has Tiptronic transmission”. In fact, this term is Porsche’s registered trademark licensed to VW Group and Land Rover. Many use this term erroneously when it comes to the usual automatic transmission with manual down and up switching (+ – mode on transmission). Such a function – to make gear shifting at the driver’s disposal (transmission + – mode) is in fact in many transmissions.
It was once a strong sales argument and was also reflected in sounding terms:
VW, Audi, SEAT – Tiptronic
Kia – Sportmatic
BMW – Steptronic
Chrysler – AutoStik
Mercedes – G tronic
Nissan – Dualmatic
Toyota – ECT
Volvo – Geartronic
Saab – Sentronic
Opel – ActivSelect
Peugeot – 2Tronic
Mazda – ActiveMatic
Mitsubishi – INVECS ja Sporttronic; jne.
ADVANTAGES – comfortable standing start, high torque resistance, switching gears under heavy load.
DISADVANTAGES – expensive and complicated to produce, big weight, lower efficiency (in previous generations of transmissions), complicated and expensive to repair.
If interested, you can watch this video: