Worm Gears

Posted on: February 25, 2022

Worm gear units.

I have a bit of a love-hate relationship with them.

As a single-stage unit, they are normally available from a ratio 7 up to ratio 100. As a right-angled unit they are very versatile and like bevel helical offer an easy mounting arrangement using the hollow bore and a torque arm.

They are easily mounted, light, cost-effective and offer a natural anti-run back, however the reason I like them creates a reason to hate them, that reason is efficiency. In the worst case, a ratio 100:1 can be as low as 30% efficient. I always try to design or select a system that is as efficient as possible, therefore sometimes I avoid worm gears. Occasionally this lack of efficiency plays into our hands and offers an advantage by not allowing it to be back-driven. For example in lifts, winches, skip drives etc it can act as a natural run back in addition to a safety brake, meaning the load does not move unless being driven by the motor. Often these loads are not full s1 duty therefore efficiency is not a big factor.

The fact the worm gear can’t be back-driven is advantageous on some incline conveyors and overrides the need for a backstop clutch.

We sell lots of them and like most things have pros and cons so it is about marrying them to the right application.

Want to find out more? DM me or contact us – sales@technidrive.co.uk

#design #wormgear #engineering