Subject: Kinematics of Machinery

Topic: Gears and Gear Trains

Difficulty: High

Involute Gear Profile:

1. Pressure angle remains same throughout the operation.
2. Teeths are weaker.
3. It is easier to manufacture due to convex surface.
4. The velocity is not affected due to variation in centre distance.
5. Interference takes place.
6. More wear and tear as contact takes place between convex surfaces.

Cycloid Gear Profile:

1. Pressure angle keeps on changing during the operation. The angle is maximum at the start and end of engagement. It is zero at pitch point.
2. Teeths are stronger.
3. It is difficult to manufacture due to requirement of hypocycloid and epicycloids..
4. The centre distance should remain the same.
5. There is no interference.
6. Less wear and tear as concave flank makes contact with convex flank.