Planetary Gearbox
What is it?

A planetary gear set is used to transfer power and multiple torque variations
to the drive axle in a small package.

It consists of three parts:
a.
Sun gear,
b.
Planet gears
c.
Ring gear
d.
Planet carrier
How does it Work?

The planetary gear set works on varying 3 members:

Ring

Carrier

Sun gear

Depending on which member is held we shall get a torque reduction(speed
increases) or speed reduction(torque increases)

Out of the three members:
o
1 member->Input
o
2 member->Held(Not Allowed to move)
o
3 member->Output
Planetary Gear Operation Table:
Sun Gear
Carrier
Ring Gear
Speed
Torque
Direction
INPUT
OUTPUT
HELD
MAX
REDUCTION
INCREASES
SAME
OUTPUT
INPUT
HELD
MAX
INCREASE
REDUCTION
SAME
INPUT
HELD
OUTPUT
REDUCTION
INCREASE
REVERSE
OUTPUT
HELD
INPUT
INCREASE
REDUCTION
REVERSE
HELD
OUTPUT
INPUT
MINIMUM
REDUCTION
INCREASE
SAME
HELD
INPUT
OUTPUT
MINIMUM
INCREASE
REDUCTION
SAME
Note:

When NO member is held together, there is NO output i.e. Neutral Condition

When any 2 members are HELD together, the speed and direction is SAME as
INPUT i.e. Direct drive(1:1)
Thank
You