Base helix angle - virtual helical gear

For the calculation of the power loss, the sliding and rolling motions must be recorded. For hypoid gears, this is done by calculation on the virtual crossed axes helical gears, which has the same sliding conditions at the calculation point as the hypoid gears. For bevel gears, the virtual crossed axes helical gears corresponds to the virtual  cylindrical gears. The calculation of the geometry parameters of the virtual gears is carried out according to G. Niemann, H. Winter: "Maschinenelemente", Vol. III, Springer-Verlag Berlin Heidelberg 1986.