advantage
1. Good meshing performance, low vibration, low noise, and smooth transmission.
2. High overlap ratio. This reduces the load on each pair of teeth, relatively increasing the gear's load-bearing capacity and extending its service life;
3. Due to the surface contact, the force-bearing area is large, and the transmission torque is large, so it is often used in heavy machinery;
4. The minimum allowable number of teeth for helical gears is less than that for spur gears, so helical gears are less prone to undercut.
5. Helical gear mechanisms are more compact, smaller in size, lighter in weight, and have higher transmission accuracy than spur gears.