There are two issues regarding tooth shape. ДЇurthermore, those 'involute bevel gear sets' cause more noise. Simplified calculated bevel gears on the basis of an equivalent cylindrical gear in normal section with an involute tooth form show a deviant tooth form with reduced tooth strength by 10-28% without offset and 45% with offset. IMPORTANT: For 5-axis milled bevel gear sets it is important to choose the same calculation / layout like the conventional manufacturing method. a triangle wave projected on the normal path of a circle of a sphere).ДЄll traditional bevel gear generators (such as Gleason, Klingelnberg, Heidenreich & Harbeck, WMW Modul) manufacture bevel gears with an octoidal tooth profile. a triangle wave projected on the circumference of a circle), whereas the bevel gear tooth profile is an octoid (i.e. The cylindrical gear tooth profile corresponds to an involute (i.e. Hypoid gears were widely used in automobile rear axles.ДЄ double-helical bevel gear made by CitroГ«n in 1927 for the MiЕ™ejovice water power plant If the beveled surface is made parallel with the axis of rotation, this configuration resembles a worm drive. The pinion can be offset above or below the gear center, thus allowing larger pinion diameter, longer life, and smoother mesh.

Hypoid bevel gears are similar to spiral bevel, but the pitch surfaces are hyperbolic and not conical.

Zerol bevel gears can be thought of as spiral bevel gears, which also have curved teeth, but with a spiral angle of zero, so the ends of the teeth align with the axis.

Zerol bevel gears are very similar to a bevel gear, but the teeth are curved: the ends of each tooth are coplanar with the axis, but the middle of each tooth is swept circumferentially around the gear.

Spiral bevel gears have curved teeth at an angle allowing tooth contact to be gradual and smooth.

Straight bevel gears have conical pitch surface and teeth are straight and tapering towards apex.

That's why this type of bevel gear is called a crown gear.Д«evel gears are classified in different types according to geometry: The use of a genuine bevel gear has even greater importance for the reliability of the axle than any other spare part.Д«evel gears that have pitch angles of greater than ninety degrees have teeth that point inward and are called internal bevel gears.Д«evel gears that have pitch angles of exactly 90 degrees have teeth that point outward parallel with the axis and resemble the points on a crown. 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. This type of bevel gear is called external because the gear teeth point outward. The most familiar kinds of bevel gears have pitch angles of less than 90 degrees and therefore are cone-shaped. The pitch angle of a gear is the angle between the face of the pitch surface and the axis. The pitch surface of an ordinary gear is the shape of a cylinder. The pitch surface of a gear is the imaginary toothless surface that you would have by averaging out the peaks and valleys of the individual teeth. Two important concepts in gearing are pitch surface and pitch angle.

7.1 Materials used in gear manufacturing process.

Gleason gear design manual