Because spiral bevel gears do not have the offset, they have less sliding between your teeth and are more efficient than hypoids and produce less heat during procedure. Also, one of the main benefits of spiral bevel gears is the relatively large amount of tooth surface that’s in mesh throughout their rotation. Because of this, spiral bevel gears are an ideal option for high swiftness, high torque applications.
Spiral bevel gears, like various other hypoid gears, are designed to be what’s called either right or left handed. A right hand spiral bevel gear is defined as having the external half of a tooth curved in the clockwise direction at the midpoint of the tooth when it is viewed by searching at the face of the apparatus. For a left hand spiral bevel equipment, the tooth curvature would be in a counterclockwise direction.
A gear drive has three main functions: to improve torque from the generating equipment (electric motor) to the driven apparatus, to lessen the speed produced by the engine, and/or to improve the direction of the rotating shafts. The connection of this equipment to the 
apparatus box can be achieved by the use of couplings, belts, chains, or through hollow shaft connections.
Swiftness and torque are inversely and proportionately related when power is held constant. Therefore, as acceleration decreases, torque raises at the same ratio.
The heart of a gear drive is actually the gears within it. Gears work in pairs, engaging one another 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 create radial reaction loads on the shaft, but not axial loads. Spur gears have a tendency to end up being noisier than helical gears because they function with a single line of contact between the teeth. While the tooth are rolling through mesh, they roll off of connection with one tooth and accelerate to get hold of with another tooth. This is unique of helical gears, that have more than one tooth connected and transmit torque more easily.
Helical gears have teeth that are oriented at an angle to the shaft, as opposed to spur gears which are parallel. This causes more than one tooth to be in contact during procedure and helical gears can handle transporting more load than spur gears. Due to the load sharing between teeth, this arrangement also enables helical gears to operate smoother and quieter than spur gears. Helical gears produce a thrust load during operation which needs to be considered if they are used. Many enclosed gear drives use helical gears.
Double helical gears are a variation of helical gears where two helical faces are placed next to each other with a gap separating them. Each helical spiral bevel gear motor encounter has identical, but reverse, helix angles. Employing a double helical set of gears eliminates thrust loads and offers the possibility of even greater tooth overlap and smoother operation. Just like the helical gear, dual helical gears are generally found in enclosed gear drives.
Herringbone gears are extremely like the double helical gear, but they do not have a gap separating the two helical faces. Herringbone gears are typically smaller compared to the comparable dual helical, and so are ideally suited for high shock and vibration applications. Herringbone gearing is not used very often due to their manufacturing problems and high cost.
As the spiral bevel gear is truly a hypoid gear, it is not always seen as one because it does not have an offset between the shafts.
The teeth on spiral bevel gears are curved and have one concave and one convex side. There is also a spiral angle. The spiral angle of a spiral bevel gear is thought as the angle between the tooth trace and an component of the pitch cone, similar to the helix angle found in helical gear teeth. In general, the spiral angle of a spiral bevel equipment is defined as the mean spiral angle.