Over pin (ball) measurement - Gear Terminology
Over pin (ball) measurement is a type of gear tooth thickness measurement method, along with chordal tooth thickness measurement and span measurement of teeth.
For example, in the case of spur gears, the tooth thickness is determined by inserting pins or balls into the tooth grooves facing each other when the number of teeth is even, or 180/z(°) when the number of teeth is odd, and measuring the outer dimension (or inner dimension in the case of internal gears) using a measuring instrument such as a micrometer.
Over pin (ball) measurement