What is the main reason for using helical-cut gears in a transaxle?

Helical-cut gears are primarily used in a transaxle due to their ability to reduce gear noise. The design of helical gears, which feature teeth that are angled relative to the axis of rotation, allows for a smoother and more gradual engagement of the gear teeth during operation. This design minimizes abrupt contact points compared to straight-cut gears, leading to reduced vibrations and noise as the gears mesh.

Additionally, the overlapping contact of the helical teeth spreads the load across more than one tooth at a time, thus resulting in less shock and noise during operation. This design characteristic makes helical gears particularly advantageous in applications where noise reduction is important for driver comfort and overall vehicle experience.