Butler Gear Blog

Identifying and Mitigating Gear Manufacturing Backlash

Thu 15th Aug 2019 at 1:56pm, 0 comments

At Butler Gear, our top priority is the satisfaction and convenience of our clients. Whether we're providing you with custom gears, broaching, hobbing, CNC milling and turning or any of our other services, we focus on every little detail of the process to ensure you get the highest-quality materials for your next project.

When it comes to gear manufacturing, one of our specialties, one of the top considerations we keep in mind is the potential for backlash. Too much or too little backlash can be an issue in many gear systems, but we have several techniques available that will help ensure the proper backlash is both achieved and optimized during any gear-related process. Let's go over the basics of what backlash refers to and the purpose it can serve in some gear systems, plus a simple primer on how we handle backlash within our various systems.

Backlash Basics

Gear backlash is actually something that occurs in every gear system to some degree or another. The term may actually be used to refer to a couple different specific things:

An error in gear motion where two or more gears are moving simultaneously when they shouldn't be.
The small spaces located between gears, spaces that are often responsible for the error in motion described above.

As we noted, backlash is common in all gear systems. It's potentially most risky, however, in systems that have reverse-direction gears. The more backlash found in gear systems, the more "slop" takes place when the system reverses.

Non-Backlash Systems - Realistic?

Theoretically, it should be possible to make a gear system, even one where gears reverse, that contains no backlash at all. This would require complete perfection in manufacturing, with no lubricant used and no thermal expansion or retraction whatsoever taking place.

Sadly, this just isn't realistic given modern manufacturing capabilities. This kind of perfection really isn't possible, despite great levels of precision we and other gear manufacturers can achieve. Instead, the industry-wide focus in this area has long been minimizing - or optimizing, in some cases - backlash within a gear system.

Minimizing Backlash

For some applications, backlash isn't significant and doesn't need to be mitigated. In others, though, there are a couple techniques that can be used to minimize or optimize it:

Splitting gears: In some applications, you can split gears on a perpendicular plane to the axes, then use springs along with each half to bring additional torque to the system.
Taper teeth: In other areas, you might consider tapering gear teeth in the axial direction, then letting the gear slide in that same direction to provide some slack to the system, thereby minimizing the impact of backlash.

For more on gear backlash and how to deal with it, or to learn about any of our custom gear manufacturer services, speak to the staff at Butler Gear today.