ME 371 Chapter Notes - Chapter 10: Fatigue Limit, Standard Deviation, Velocity Factor

• School: University of Illinois
• Department: Mechanical Engineering
• Course: ME 371
• Professor: A Dunn

Document Summary

They transmit power between parallel shafts through the sequential contact of the gear teeth. The basic requirement for functioning gears is that the ratio of rotational speeds, , matches the ratio of number of teeth, n; if this requirement is not met, the teeth will slip, and no power will be transmitted. We represent this ratio mathematically between a gear (subscript g) and a pinion (subscript p) mathematically as p g. The negative sign is used to indicate that the gears rotate in opposite directions. We also characterize each gear by the pitch diameter d, which describes the pitch circle, the shape we use to represent the contact between two gears as touching circles. If there is no other descriptor of a gear diameter, assume it is the pitch diameter. The number of teeth and the diameter of mating gears have to be designed with the same metric, called the diametral pitch, or simply pitch, p.