Skew bevel gears are those for which the corresponding crown equipment has the teeth that are straight and oblique.

Mitre gears are mating bevel gears with equal amounts of teeth and with axes in right angles.

Bevel gears which have pitch angles of precisely 90 degrees possess teeth that point outward parallel with the axis and resemble the points on a crown. That is why this kind of bevel gear is named a crown gear.

Bevel gears that have pitch angles in excess of ninety degrees have teeth that point inward and so are called internal bevel gears.

The most familiar kinds of bevel gears have pitch angles of less than 90 degrees and therefore are cone-shaped. This kind of bevel gear is named external since the gear teeth stage outward. The pitch areas of meshed external bevel gears are coaxial with the apparatus shafts; the apexes of both areas are at the idea of intersection of the shaft axes.

Two important principles in gearing are pitch surface and pitch angle. The pitch surface area of a gear is the imaginary toothless surface area that you would possess by averaging out the peaks and valleys of the average person teeth. The pitch surface area of a typical gear is the form of a cylinder. The pitch angle of a equipment is the angle between your encounter of the pitch surface and the axis.