External versus internal gearsExternal gears are gears with teeth formed on the outer surface of a cylinder or cone. In contrast, an internal gear is a gear with teeth formed on the inner surface of a cylinder or cone. As with bevel gears, internal gears are gears with pitch angles greater than 90 d

GMM Universal Gear Detector is a new type of intelligent gear measuring instrument. It adopts the measurement principle of electronic generation, does not require base disc and reference detection components, and has high detection accuracy. It can detect involute cylindrical spur teeth, helical teeth, and it can complete the measurement of the tooth shape, tooth direction and pitch error of the involute gear under the condition of one clamping.