A Sun Gear is a component of a planetary gear unit, which is a type of gear unit comprised of spur gears. The sun gear is located in the center of the planetary gear set and takes a high-speed, low-torque input. Its load is distributed to several planetary gears, which can either be used to drive an outer ring or a shaft, or a spindle. It is typically made up of steel.

Attributes:
• Drives several rotating external gears, which increases the torque
• Heat treated with Surface hardening that provides excellent hardness

Applications:
A Sun Gear is used in mechanical power transmission.