WD Secondary Worm Gear Assembly

Spur gears are gears that drive between two parallel shafts, and are also easily imagined and common gears. Since the tooth flanks are parallel to the axis of the assembly shaft, spur gears generate no thrust (axial force) in the gearbox. In addition, due to the simple processing of spur gears, gears with high precision can be manufactured.
It is not limited to spur gears, but is often used to handle gears that require a slight change in center distance and increased gear strength. Displacement is achieved by adjusting the distance between the hob and the gear. Positive displacement results in increased flexural strength of the gear, negative displacement results in a slight reduction in the center distance. Backlash is the gap between the tooth surfaces of a pair of gears when they mesh. Backlash is very necessary if you want a pair of gears to mesh and rotate smoothly. However, the existence of cogging makes the meshing worse and the noise increases, thus reducing the transmission accuracy. On the contrary, if the tooth pitch is too small, it is easy to cause poor lubrication and damage to the gear.