Ruuvipykäläpyörät

Ruuvipykäläpyörät, a Finnish term, translates to "screw thread gears" or "helical gears" in English. These are a type of gear where the teeth are cut at an angle to the face of the gear, forming a helix. Unlike spur gears which have teeth parallel to the axis of rotation, the angled teeth of helical gears allow for smoother, quieter operation and can transmit greater loads.

The helix angle is the angle between the axis of the gear and the helix of the tooth. A smaller helix angle results in performance closer to that of a spur gear, while a larger angle increases contact ratio and torque capacity but also introduces axial thrust. This thrust must be accommodated by suitable bearings.

Helical gears can be manufactured in both right-hand and left-hand helix directions. When two helical gears mesh, they must have opposite hand helix angles to transmit motion effectively. This counteracting helix angle also helps to balance the axial thrust.

The design of helical gears allows for gradual engagement of teeth, which reduces shock and vibration compared to the sudden engagement of spur gears. This makes them ideal for applications requiring smooth power transmission, such as in automotive transmissions, industrial machinery, and high-speed applications. The ability to handle higher loads and operate more quietly are their primary advantages.