Sorting out gearhead semantics

In machine design, engineers must often use precision gearheads especially when servo motors are used. Precision gearboxes allow the motors to operate much more economically. When determining what type of gearhead to use, factors of backlash, lost motion, repeatability, and precision should be examined first. These factors will severely impact efficiency if the designers are not careful. Backlash occurs when a gear tooth has extra space when engaging a tooth slot. Because the tooth has extra play within the slot, there will be some lost motion as the output rotates but the input does not. Backlash is not a problem if the gear is only rotating in one direction, but the effects are noticed when the motion is reversed. Of course, backlash can never be totally avoided and some is actually necessary to provide space for lubricant and thermal expansion. There are some steps that can be taken to maximize gear stiffness and reduce backlash which the article explains further. Repeatability and precision of a gearhead are impacted by the position of gear teeth. Inaccurate gear teeth will cause the servo motor to also be inaccurate and also could lead to machine fatigue.   Read the full article at Machine Design.

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