Why do automatic transmission have planetary gear sets?
The planetary gear set is really the heart of an automatic transmission. This one part creates all the possible gear ratios that the transmission can produce.
What is the purpose of planetary gears?
Generally, planetary gears are used as speed reducers. They are used to slow down motors and increase the torque. Torque is the working power of the machine.
How do planetary gears shift?
As mentioned above, the central “sun” gear is usually the input gear. As the sun gear turns, it causes the planet gears to rotate in place along the inside of the ring. This motion, in turn, rotates the output shaft in a reverse direction.
What are the advantages of epicyclic gear train?
Advantages of Epicyclic Gearbox : Compact and lightweight with high torque transmission. High radial loads on the output shaft. It is quieter in operation. Uniform distribution of load over all gears having greater tooth contact.
How efficient are planetary gears?
The efficiency loss in a planetary gear train is typically about 3\% per stage. This type of efficiency ensures that a high proportion (about 97\%) of the energy being input is transmitted through the gearbox, rather than being wasted on mechanical losses inside the gearbox.
How many gears does an automatic transmission have?
Contemporary automobile manual transmissions typically use four to six forward gear ratios and one reverse gear, although consumer automobile manual transmissions have been built with as few as two and as many as seven gears.
What is the purpose of the planetary gears?
Planetary gears are at the heart of modern engineering and are used in gearboxes that power everything from basic plant machinery to cutting-edge electric vehicles. The simple configuration of a central drive and orbiting gears was developed thousands of years ago to model the movements of the planets .
What causes automatic transmission to stop shifting gears?
If an automatic transmission has trouble shifting gears, it could be because the transmission fluid is low, the fluid is the wrong viscosity or the throttle cables need adjusting.
Is engine braking bad for automatic transmission?
Engine braking is not just useful for transmission and brake pad wearing but also, improves the fuel economy, as your car wouldn’t have to come to a hard stop, which would require re-accelerating each time when you step on the gas pedal.