Gears. Inter American University of Puerto Rico Mechanism Design MECN 4110. Chapter 9. Mechanical Transmissions. Belts. Chains. Gears. Types of Gears. Spur Gears. Pinion. Gear. Spur Gears - Types. External Set: Opposite Movement. Internal Set: Movement in the same direction.
Inter American University of Puerto Rico
External Set: Opposite Movement
Internal Set: Movement in the same direction
The involute is a curve which can be generated by unwrapping a taut string from a cylinder (called the evolute). Features of this involute curve:The Involute Tooth Form
If mp is 1, then one tooth is leaving contact just as the next is beginning contact. Spur gears [1-2]. The minimum contact ratio for a smooth operation is 1.2. A minimum contact ratio of 1.4 is preferred and larger is better. Most spur gearsets will have contact ratios between 1.4 to 2.