“PLAY”ing with Backlash to optimize a dynamic servo, planetary or cycloidal gearbox.

Understanding backlash and how it is measured is a critical element when trying to optimize a dynamic servo, planetary or cycloidal gearbox

What is Gearbox Backlash?

Backlash is defined as the play resulting from clearance or play between gears or other mechanical elements of a gearbox. Backlash is minimized in planetary gearboxes by maximizing the quality of the gear geometry and precisely controlling the mating parts.

Backlash Unit of Measure

Backlash is measured in arc-minutes.
1 arc-minute = 1/60th of 1 degree or .0167 degree.

Measuring Backlash in Cycloidal and Planetary Gearboxes

Backlash in a gearbox is measured by locking the input shaft against rotation and applying a measured force to the output shaft. By using a load cell and potentiometer, a plot can be created. Backlash occurs at close to zero load when rotation is reversed.

In cycloidal gearboxes, backlash is minimized because of the high number of contact points of the gears. Backlash can also be eliminated by preloading the force transmitting components.

Onvio Gearbox Backlash Measurement Facts

In order to measure backlash accurately, it is important to capture all of the free play between the gears without measuring torsional wind-up of the gearbox. To insure accurate measurements, Onvio performed a variety of tests during development to arrive at the appropriate torque levels at which to measure backlash. We measured backdriven torque of the gearbox to determine the frictional forces that needed to be overcome to engage all gears resulting in rotation the input shaft relative to output rotation at the lowest possible load (typically 1-2% of rated load).

backlash chart

Zero Backlash Cycloidal Gearbox / Speed Reducers

Did you know that Onvio’s Dojen™ cycloidal gearbox / speed reducer is the highest precision servo reducer available on the market.  It offers TRUE Zero backlash by combining a compound reduction cam with preloaded, full compliment needle bearing cam followers. All force transmitting components are in constant contact!   Learn more

More Questions about Measuring Backlash in a Gearbox?

Let Onvio’s team of engineers work for you.

Please call 866 685-0404 (toll free),
603 685-0404, or fax 603 685-0405
or, email: contact@onviollc.com

Onvio LLC Headquarters
20 Northwestern Drive, Salem, NH 03079