Because spiral bevel gears do not have the offset, they have less sliding between the teeth and are better than hypoids and generate less heat during operation. Also, one of the main advantages of spiral bevel gears may be the relatively large amount of tooth surface that’s in mesh throughout their rotation. For this reason, spiral bevel gears are a perfect option for high velocity, high torque applications.
Spiral bevel gears, like other hypoid gears, are designed to be what’s called either right or left handed. A right hand spiral bevel equipment is thought as having the external half of a tooth curved in the clockwise path at the midpoint of the tooth when it’s viewed by searching at the facial skin of the gear. For a left hand spiral bevel equipment, the tooth curvature will be in a counterclockwise path.
A gear drive has three main functions: to improve torque from the generating equipment (engine) to the driven devices, to lessen the speed generated by the electric motor, and/or to change the path of the rotating shafts. The bond of the equipment to the apparatus box can be accomplished by the use of couplings, belts, chains, or through hollow shaft connections.
Rate 
and torque are inversely and proportionately related when power is held constant. Therefore, as velocity decreases, torque increases at the same ratio.
The center of a gear drive is actually the gears within it. Gears function in pairs, engaging each other to transmit power.
Spur gears transmit power through shafts that are parallel. One’s teeth of the spur gears are parallel to the shaft axis. This causes the gears to produce radial reaction loads on the shaft, however, not axial loads. Spur gears tend to become noisier than helical gears because they work with a single line of contact between tooth. While the the teeth are rolling through mesh, they roll from contact with one tooth and accelerate to get hold of with the next tooth. This is different than helical gears, that have several tooth in contact and transmit torque more efficiently.
Helical gears have teeth that are oriented at an angle to the shaft, unlike spur gears which are parallel. This causes several tooth to be in contact during operation and helical gears can handle transporting more load than spur gears. Because of the load posting between teeth, this set up also enables helical gears to operate smoother and quieter than spur gears. Helical gears create a thrust load during procedure which needs to be considered if they are used. Most enclosed gear drives use helical gears.
Double helical gears certainly are a variation of helical gears where two helical faces are positioned next to each other with a gap separating them. Each encounter has identical, but reverse, helix angles. Employing a double helical set of gears eliminates thrust loads and will be offering the possibility of sustained tooth overlap and smoother operation. Like the helical gear, double helical gears are generally found in enclosed gear drives.
Herringbone gears are extremely like the double helical equipment, but they do not have a gap separating both helical faces. Herringbone gears are usually smaller than the comparable dual helical, and so are ideally fitted to high shock and vibration applications. Herringbone gearing isn’t used very often because of their manufacturing problems and high cost.
While the spiral bevel gear is truly a hypoid gear, it is not helical spiral bevel gear motor always viewed as one because it doesn’t have an offset between the shafts.
One’s teeth on spiral bevel gears are curved and have one concave and one convex side. There is also a spiral position. The spiral angle of a spiral bevel equipment is thought as the angle between the tooth trace and an component of the pitch cone, like the helix angle found in helical gear teeth. Generally, the spiral angle of a spiral bevel gear is defined as the imply spiral angle.