20Cr2Ni4 Steel Precision Spur Gears 10 Module 24T For Transmission Speed Reducers

10 Module 24T Gear Grinding Planetary Gear For Transmission Speed Reducers

1) Types of Spur Gears

There are two primary types of spur gears: external and internal. External gears have teeth that are cut

on the outside surface of the cylinder. Two external gears mesh together and rotate in opposite directions.

Internal gears, in contrast, have teeth that are cut on the inside surface of the cylinder. An external gear

sits inside the internal gear, and the gears rotate in the same direction. Because the shafts are positioned

closer together, internal gear assemblies are more compact than external gear assemblies. Internal gears

are primarily used for planetary gear drives.