Bevel gear ordinary gear is the shape of a cylinder. The pitch angle of a gear is the angle between the face of the pitch surface and the axis. The most familiar kinds of bevel gears have pitch angles of less than 90 degrees and therefore are cone-shaped. This type of bevel gear is called external because the gear teeth point outward. The pitch surfaces of meshed external bevel gears are coaxial with the gear shafts; the apexes of the two surfaces are at the point of intersection of the shaft axes. Bevel gears that have pitch angles of greater than ninety
Nambu Type 90 than the Imperial Army's Type 10 for a few good reasons. First, they were made in lower numbers than the Army type. Second, they were usually issued to ships and Naval aircraft and were lost when they were destroyed or sank. Third, Soldiers and Marines who found flare guns on the battlefield often threw them away, as they were not seen as collectable as pistols, rifles, or knives. In Hollywood movies (like "Demolition Man (1993)" and "Waterworld (1995)"), the Type 90 is used erroneously as a stand-in for a futuristic shotgun pistol. Nambu Type 90 The Nambu Type 90 was