A planetary electric motor (PEM) generates planar orbital and variable oscillatory motion without gearboxes, cranks, rotating components, eccentric weights, or bearings. These qualities make the VibraQ from VibraQ Corp. Ltd., Western Australia, (vibraq.com) well suited for vibrating and mixing equipment. Electronic controls let it instantaneously switch between an array of geometric patterns such as circular, elliptical, or linear at almost any needed vibration frequency. The motor produces these motions with dynamic control over displacement and frequency of the working platform. Traditional cranked or counterweighted methods of generating planar-orbital motions suffer from bearing failures, inefficiencies due to fixed motions, and mechanical complexity.

Synchronous motors, often used in vibrating equipment, rely on a stationary armature that sees a changing flux while the rotor sees a steady flux state and turns. In the VibraQ motor, the armature moves and is exposed to a changing flux, while the stator, made of permanent magnets, is stationary and has an unchanging flux.

The new motors can output dynamically variable motion, control the orbit diameter and frequency, and put out full force at standstill. In addition, the design resists burnout, runs silently, and avoids harmonics.