Bevel gears are of help when the direction of a shaft’s rotation must be changed. They are often installed on shafts that are 90 degrees aside, but could be designed to work at Rotary Air Compressor 
various other angles as well.
The teeth on bevel gears can be direct, spiral or hypoid. Right bevel gear teeth actually have the same problem as straight spur gear teeth — as each tooth engages, it impacts the corresponding tooth all at once.
Just like with spur gears, the solution to the problem is to curve the gear teeth. These spiral tooth engage exactly like helical tooth: the contact starts at one end of the gear and progressively spreads across the whole tooth.
On straight and spiral bevel gears, the shafts should be perpendicular to one another, but they must be in the same plane. In the event that you were to extend the two shafts at night gears, they would intersect. The hypoid gear, on the other hand, can build relationships the axes in different planes.
Hypoid bevel gears in a car differential
This feature is used in lots of car differentials. The ring equipment of the differential and the insight pinion gear are both hypoid. This enables the input pinion to be installed lower than the axis of the band gear. Figure 7 shows the input pinion engaging the ring equipment of the differential. Since the driveshaft of the automobile is connected to the insight pinion, this also lowers the driveshaft. This implies that the driveshaft doesn’t intrude in to the passenger compartment of the automobile as much, making more room for people and cargo.