Transmissions: Automatic Transmissions: Planetary gearing

Planetary gears	A simple planetary gearset has a sun gear, planet pinions mounted on a planet carrier, and a ring gear.
Simple planetary gearsets	A simple planetary gearset can illustrate how to control individual members to produce a particular drive output, or neutral.
Compound planetary gearsets	The Ravigneaux and Simpson gearsets are examples of compound planetary gearsets which are used in automatic transmissions.
Automatic transmission brake bands	Brake bands in automatic transmissions are externally contracting types which are operated by hydraulic servos.
Multi-disc clutches	In most transmissions, planetary gear members and shafts are coupled together by multiple-disc clutches. They can also hold members to the case instead of using bands.
Plate clearance	In the released position, the plates must retain a set clearance. This allows them to separate from one another and avoid excessive or premature wear.

Topic	Summary