At times a motor’s capability may be limited to the point where it requires gearing. As servo manufacturers develop more powerful motors that can muscle applications through more complicated moves and produce higher torques and speeds, these motors require gearheads equal to the task.
Interestingly, only about a third of the motion control systems in service use gearing at all. There are, of course, good reasons to do so. Using a gearhead with a servo motor or using an integrated gearmotor can enable the use of a smaller motor, thereby reducing the system size and cost. There are three primary advantages of going with gears, each of which can enable the use of smaller motors and drives and therefore lower total system cost:
Torque multiplication. The gears and number of teeth on each gear create a ratio. If a motor can generate 100 in-lbs of torque, and a 5:1 ratio gear head is attached to its output, the resulting torque will be close to 500 in-lbs.