Cylindrical gears are the most widely used gears and they represent the lion’s share of the whole gear market. They are gears with teeth arranged on a cylindrical surface. There are two main cylindrical gear families:
- Spur gears
- Helical gears
These two families rely on the teeth profile shape, which can be either straight or parallel to the axis for the former or set at an angle to the gear axis for the latter. Since the teeth engagement in helical cylindrical gears is gradual – as opposed to spur gears where the entire face engages at once –helical gears operate with less noise.