How To Get Zero Backlash In A Gearbox

Gears are used by gearmotors in order to reduce speed. This offers more torque. The type of gears that are used in a gearmotor impacts available torque but it also influences other things, like accuracy and noise levels.

The really common source of an inaccuracy in a gearmotor is gear backlash. Because of this, reducing backlash amounts creates an accurate gearmotor.

Understanding Backlash

Before you check out the zero backlash gearbox on this page, it is important to understand backlash. This is possible only if you understand gearhead mechanics.

The gearbox is made out of different mechanical components, like bearings, wheels, pulleys and so on. The exact combination used in a project varies based on reducer type. What is always common is that the intended use is to transmit power. This is done from motor output towards a load. The goal is to increase torque and reduce speed in a consistent and safe manner.

Backlash can be defined as the gap present between tail edge tooth that transmits power and the edge of the next edge. This gap is very important in a gear as it makes it easier to mesh without being stuck. It is also used to add lubrication.

When losses appear, precision and efficiency are negatively impacted. Backlash is increased by manufacturing inconsistencies, misalignment and incorrect tolerances. It is not possible to completely get rid of backlash. However, it is possible to minimize it so it reaches a value close to zero. This is what people mean when they say “zero backlash”.

How To Achieve Zero Backlash

There are different ways to reduce the backlash seen in gears. This includes pre-loading and designing with the use of gears that minimize backlash, as much as possible.

Precision gears are highly recommended in order to reduce backlash. When manufactured, companies use really high tolerances. Gears are tighter and much more precise to easily fit. Since there is a tighter fit present, gear teeth show less play. Obviously, using precision gears is more expensive. However, when high accuracy is paramount for the application, using the precise gears is mandatory.

Whenever looking at gear design, a very simple way to drastically reduce backlash is to design in such a way that teeth tightly mesh together. Manufacturers do this by simply shortening the distance present between the gears. When referring to pre-loading, a spring mechanism is used in order to firmly hold the gears in place. This method can also eliminate gear teeth play to drastically reduce backlash.

The gears that are used in an application always have a huge impact on backlash amount. For instance, there are some gears (like harmonic gear drives or strain wave gears) that naturally come with zero backlash.


Although achieving zero backlash is close to impossible, due to the work of numerous manufacturers, nowadays backlash is very low. One of the most important things to understand is that in order to achieve really low backlash, the system has to use gears that are created for this very purpose.

I am content write and technical expert at a tech organization. I also do the computer science education through the college. Love to solve the techncal issue through my writing and want to help people to solve their.

Write A Comment