The name of helical gear is mainly different from spur gear. As the name suggests, it is "gear with inclined teeth". The tooth surface of this kind of gear is not parallel to the axial direction, but has a certain included angle. It is precisely because of this included angle that helical gear has a variety of characteristics different from spur gear.
Što se tiče poboljšanja performansi, spiralni zupčanik ima veći stupanj koincidencije od cilindričnog zupčanika (povećava se s povećanjem širine zupčanika i kuta spirale), što donosi jaču nosivost vozila i veći krajnji zakretni moment koji se može opteretiti. Stoga ima očite prednosti u području velike-brzine i velikog opterećenja.
