While worm gears may not be the most efficient of gear types, there are some applications where worm gears are particularly practical, such as gates, conveyors, lifts and elevators, just to name a few.
Worm Gear Drive Design
The basic design of a worm gear consists of two parts: a steel worm gear and a bronze worm wheel. The two different metals help to improve the otherwise low efficiency of the worm gear design that is due to the sliding action of the two gears.
Worm gears are designed in a way that allows for a high total gear ratio with a small number of gear sets. This results in the ability to achieve low output speeds and high output torque. It also allows for the lower output speed and increased torque to be achieved in a small gear housing.
It is often difficult to reverse the direction of torque transmission when worm gears are used. This can provide a self braking action that is useful for a number of lifting and hoisting applications.
Worm Drive Applications
Worm gears are beneficial for a range of industrial applications:
- Applications where fast braking or stopping is desired — Lifts, elevators and hoists
Backdriving is nearly impossible with worm gears. Stopping and holding may be possible without an external brake, or a smaller brake could be used with the worm gear as the secondary braking system. Worm gears should not be relied on as a sold braking method.
- Applications where noise is a concern — Theaters, airports and elevators
The sliding engagement between the gear teeth in worm drives allows for quieter operation than some other gear types. The dissimilar materials used in worm gear sets also contributes to their quiet operation.
- Applications where space is a concern — Packaging equipment, small machinery and conveyors
As mentioned before, the design of a worm gear allows for fewer gear sets to be used in order to achieve high gear ratios (with significant speed reduction and torque increase). With fewer gear sets, the result is a smaller gearbox.
- Applications with shock loading — Rock crushers and other heavy duty machinery
Because one of the gears in a worm gear set is made of a softer metal, it can more easily absorb the energy from sudden shock loads.
Roger Corning, maintenance supervisor at a NORD Drivesystems customer said, "By switching to FLEXBLOC™ units, we functionally replaced four gearboxes with one, resulting in direct cost savings, less installation time and saved space."
Worm Drives and Other Gearboxes for Any Application
NORD Drivesystems creates drive solutions for conveyors, lifts, filling systems and many other industry applications.
NORD also manufactures high quality gearmotors, electric motors, speed reducers and AC Vector Drives. But NORD does far more than manufacture industry leading drive components; we provide our customers with optimum drive configurations for their specific application requirements, providing each and every one with a truly complete and efficient system.
NORD Drivesystems has over 60 assembly and service centers across the globe, and our various gear drive solutions power the world's largest shipyard portal crane in Denmark, the retractable roof of Colonial Stadium in Australia and the Corona Brewery in Mexico, just to name a few.
Connect with a NORD Drivesystems representative and make our worm gear and other gearbox applications part of your business!
Machinery Lubrication: http://www.machinerylubrication.com/Read/1080/worm-gears