Circumferential Backlash - Gear Nomenclature
Backlash refers to the play (gap) between the tooth flanks of a pair of gears when they are meshed. Among these, circumferential backlash is defined as the length of the arc of the gap at the pitch circle.
1. Circumferential Backlash
2. Normal Backlash
3. Meshing Flank
4. Meshed Flank