Monthly Archives: April 2022
The accuracy of a servo gearbox is given most commonly as backlash. Since a gearbox is a rotational device, this number is given in angular units. The typical unit of measure of precision gearboxes is arc-minutes. One arc-minute is 1/60th of a degree. The backlash of a gearbox is measured by locking the input – driven or motor side, loading the output in one direction, then loading in the opposite direction and measuring the displacement. The load used to perform the test is not arbitrary. The typical value is 1-2% of nominal torque capability. In this range, torsional windup of loading the components in the gearbox is minimized, so that purely backlash is measured. This gives the value of lost motion when there is a reversal of torque in the operation.
Contributing factors to Backlash
When considering backlash in a gearbox, we need to examine the accuracy of the individual gears that comprise the gearbox. T
