Bevel gears are useful when the direction of a shaft’s rotation needs to be changed. They are usually mounted on shafts that are 90 degrees aside, but can be designed to just work at various other angles as well.
One’s teeth on bevel gears could be straight, spiral or hypoid. Straight bevel gear teeth already have 
the same issue as straight spur equipment teeth — as each tooth engages, it impacts the corresponding tooth all at one time.
Exactly like with spur gears, the answer to this problem is to curve the apparatus teeth. These spiral tooth engage just like helical tooth: the contact begins at one end of the gear and progressively spreads across the whole tooth.
On right and spiral bevel gears, the shafts should be Motorbase perpendicular to each other, but they must also be in the same plane. If you were to lengthen the two shafts past the gears, they would intersect. The hypoid gear, on the other hand, can engage with the axes in various planes.
Hypoid bevel gears in a car differential
This feature can be used in lots of car differentials. The band gear of the differential and the insight pinion equipment are both hypoid. This allows the insight pinion to be installed lower than the axis of the ring gear. Figure 7 shows the insight pinion engaging the band equipment of the differential. Since the driveshaft of the car is connected to the input pinion, this also lowers the driveshaft. This means that the driveshaft doesn’t intrude into the passenger compartment of the automobile as much, making even more room for people and cargo.