After the large wheel blank of hypoid gear is determined, the size of small wheel blank can be determined according to the large wheel blank. The root cone of large wheel and the face cone of small wheel, the face cone of large wheel and the root cone of small wheel of hypoid gear can be regarded as two pairs of new pitch cones respectively. It is assumed that the position of the design node of the big wheel remains unchanged, and the newly formed pitch cone is still tangent to this point. The newly formed pitch cone angle is equal to the face cone angle of the big wheel, the root cone angle of the small wheel, the root cone angle of the big wheel and the face cone angle of the small wheel respectively.
According to the meshing of large and small wheels of hypoid gear at the midpoint, the tooth top height and tooth root height of small wheel at the midpoint can be obtained as follows:
The bevel angle of hypoid gear pinion is:
Where, ε F – offset angle of large axle section.
The distance from the apex of hypoid gear pinion cone to the intersection is:
The distance from the crown of hypoid gear pinion to the intersection is:
The distance from the inner crown of the hypoid gear pinion to the intersection is:
The tooth width, outer diameter and full tooth height of hypoid gear pinion are respectively:
At this point, all geometric parameters of hypoid gear pair can be calculated.