Bevel and miter gearing is a form of gearing in which the tooth-bearing surfaces are the faces of the gears rather than the edges. In bevel and miter gearing, the gears are cone shaped. This allows the edges of the mating gears to mesh and transmit torque. The geometry of the mesh creates a 90 degree angle. As a result, this type of gearing is suitable for applications where a change of direction is required. Other designs exist to create other angles however 90 degrees serves the majority of applications. In bevel and miter gearing the input and output shaft are intersecting. It is typical for bevel and miter gear reducers to have lower reduction ratios. For example, 5:1 and lower are typical and they are different than other types of gearing.
Two types of bevel and miter gearing are typical. These are straight and spiral. As the name implies, the teeth of straight bevel gears are cut straight. This means that the teeth are oriented perpendicular to the outside edge of the gear. The teeth on spiral bevel gears are cut at an angle to the outside edge of the gear. This type of gearing is said to have “helical” teeth and the angle is called the “helix” angle.
Bevel and miter gearing have proven reliable for many years. The use of this type of gearing extends across many industries. Some of these include food processing, woodworking, paper and textile. Applications include printing machines, chemical mixers, packaging machinery and roller conveyors.