Linear Motor

A motor that outputs straight-line force and motion directly, with no screw or other transmission.

A linear motor lays its stator (coils or magnetic track) and its mover out along a straight line; once powered, the mover translates directly along the track, with no lead screw, gear, or other mechanism in between to turn rotation into linear motion. The benefits are high speed, high positioning accuracy, and no backlash (transmission play), so it's widely used in semiconductor equipment, precision stages, and high-speed sorting; the downsides are low force per unit volume, high cost, and no self-locking when power is cut. A common point of confusion for newcomers: what's usually called a “linear actuator” or “electric cylinder” on a humanoid robot is almost always a rotary motor paired with a planetary roller screw, not a true linear motor.

ExampleThe precision motion stages in wafer inspection equipment are commonly driven by linear motors, paired with a linear encoder scale for micron-level positioning.

Also called

Linear Electric Motor

Related

Linear Actuator (Electric Cylinder) · Planetary Roller Screw · Ball Screw · Direct Drive · Permanent Magnet Synchronous Motor (PMSM) · Backlash

Sources

Linear motor - Wikipedia