MOTION SYSTEMS HANDBOOK
Servomotors: the basics Servomotors are used on machine axes that need to make complex moves or position loads with really high precision. Servomotors can
The Kollmorgen AKMH hygienic servomotor includes FDA-approved food-grade materials and meets IP69K, EHEDG, and 3A standards. The motor helps food processors reduce food-recall risks and decrease cleaning time. The motor can withstand 1,450 psi spray and pH 2 to pH 12 chemicals.
also run at zero rpm while holding torque to keep a load at a set position. A servomotor (or servo system) is characterized mainly by the use of closed-loop control. The system takes an error in position, speed, or torque and corrects it through the use of a feedback device. A controller compares the system’s actual performance with its commanded performance and takes corrective action to eliminate the error. A servomotor can be built around one of several types of motors. Common types include dc brushed and brushless motors as well as ac induction motors. The advantage of brushed dc servomotors is their linear and predictable performance that makes them easy to apply. Brushless motors usually run applications needing more torque; the only catch here is that their drives are more complex because commutation is done electronically and not mechanically as in brushed dc motors. What’s more, industry categorizes motors in part by their number of electrical phases. Brushed dc servomotors as well as voice coil motors are in fact single-phase motors, whereas brushless servomotors most commonly have three phases.
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DESIGN WORLD — MOTION
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