Some differences between spiral bevel gears and hypoid bevel gears

Some differences between spiral bevel gears and hypoid bevel gears are explained below for reference.

Spiral bevel gear:

The main and driven gear axes intersect at a point, and the angle of intersection can be arbitrary. However, in most automobile drive axles, the main reducer gear pair adopts a 90° vertical arrangement.

Due to the overlap of the end faces of the gear teeth, at least two or more pairs of gear teeth mesh at the same time. Therefore, the spiral bevel gear can withstand a larger load. In addition, the gear teeth are not meshed at the same time over the full tooth length, but are gradually meshed by the teeth. One end is continuously turned to the other end, so that it works smoothly, and even at high speed, the noise and vibration are very small.

Hypoid gear:

The axes of the driving and driven gears do not intersect but intersect in space, and the intersecting angles of space also adopt a 90° angle different plane vertical method.

The driving gear shaft has an upward or downward offset relative to the driven gear shaft (referred to as upper or lower offset accordingly).

When the offset is large to a certain extent, aGear shaftPass by the other gear shaft.

So that eachgearBearings with compact sizes arranged on both sides of the two sides are beneficial for enhancing the rigidity of the support and ensuring the correct meshing of the gear teeth, thereby increasing the life of the product. It is suitable for through-type drive axles.

Unlike spiral bevel gears where the helix angles of the driving and driven gears are equal because the axes of the gear pairs intersect, the axis offset of the hypoid gear pair makes the driving gear helix angle greater than the driven gear helix angle.

Therefore, although the normal modulus of the hypoid bevel gear pair is equal, the end face modulus is not equal (the end face modulus of the driving gear is greater than the end face modulus of the driven gear).This makes the driving gear of the quasi-double-sided bevel gear transmission have a larger diameter and better strength and rigidity than the driving gear of the corresponding spiral bevel gear transmission.

In addition, due to the large diameter and helix angle of the driving gear of the hypoid bevel gear transmission, the contact stress on the tooth surface is reduced and the service life is increased.

However, when the transmission is relatively small, the driving gear of the quasi-double-sided bevel gear transmission is too large compared to the driving gear of the spiral bevel gear. At this time, it is more reasonable to choose the spiral bevel gear.

Spiral bevel gears and hypoid bevel gears are the main transmission methods used in automobile final reducers. Regarding their differences, if you have more questions or related processing requirements, you can consult EP for free.