ABSTRACT
This chapter begins the discussion of involute gearing with an analysis of the specified kinematics of the relative motion of a gear and its mating pinion. Correct transmission and transformation of a steady rotation of an input shaft to a desired rotation of the output shaft is the main purpose of involute gearing. A vector diagram of a gear pair is a convenient tool for the investigation of the kinematics of parallel-axes gearing. A vector diagram is composed of two rotation vectors. One of the vectors is the rotation vector of the gear. This vector is denoted by ωg. The other is the rotation vector of the pinion. When the gears rotate, the plane of action is considered a zero-thickness film that is unwrapping from the base cylinder of the gear and wrapping onto the base cylinder of the pinion, or vice versa.
