What is a linear motor?

Motion4 LINEAR MOTORA Linear motor is an electrically-powered motor that have had its stator and rotor “unrolled” so that instead of producing a torque (rotation) it produces a linear force along its length.

Unlike rotary motors, which cause thrust through spinning elements, linear induction motors produce their thrust in a straight line. Their thrust is caused through the interaction of magnetic fields within the motors, by magnetic attraction and repulsion.

In a synchronous motor the rate of movement of the magnetic field is controlled, usually electronically, to track the motion of the rotor.

Is it a magnetic drive?

Yes, it works with the same principle as any other motor.  However on a linear motor, the magnets are placed alligned on a a flat surface, making the element that we want to move (i.e. a door leaf), slide along the line of magnets by attraction/repulsion of the same.

Does it work with magnetic levitation? No… but almost.  The attraction force of the magnets is around 40Kg. For a door leaf weighing less than 40 Kg, the magnets compenssate almost its full weight, however we still need the carriers and its wheels to guide the door leaf along the track.  Having heavy door leaves levitating at all times, even in stand-by mode would require bigger magnets and high power consumption that would make the product too expensive to maintain. Linear motor and magnetic levitation technologies share the same principle of operation, where motion is generated by the attraction and repulsion of the magnets placed in-line.

What type of motor is used in linear motors?

All Motion4 products are equipped with three phase AC motors type LSMPM – Linear Synchronous Motor with Permanent Magnets

What type of magnets are used?

Permanent Neodymium magnets, which are more powerful than other type of magnets, and keep a persistent magnetic field without loosing its properties along time.

How precise is the technology developed by MOTION4?

To obtain the maximum precision of movement of the door leaf, all EvoDrive and e-motion operators are equipped with a magnetic position feedback with 3 hall cells, with a resolution of up to 10 micrometers (µm).