Worm Face gear

Version 06.27.2022

Worm face gear is similar to High Ratio Hypoid but with involute helical worm pinion. Pressure angle on the drive and coast side is often different. 10/30 degrees pressure angle design has been dominating under trade name Spiroid of ITW in the US. This gear design is also known as SPIRSIN in Spain. The worm pinion can be cylindrical or tapered. Tapered worm can be used for zero-backlash adjustment by advancing the worm along its axis.   

Tapered worm

More teeth in the mesh for higher torque and smooth drive

More compact compared to worm gears

Involute tapered worm thread for easy machining