More than 50 000 Sodick Flat Linear Motor EDM in operation throughout the World

A Sodick machine-tool with flat linear motors is a unified mechatronic system

Sodick Flat Linear Motor in AP250L

Any Sodick linear servo drive with a flat linear motor is designed individually for the part of the machine that this drive must move in the machine. But this driven body of the machine, whether it is the carriage of the X or V, or Z axis, is initially designed for this drive. In Sodick linear machines, the motors always correspond to their parts of their machine, just as the machine itself is designed for its motors. In other words: A Sodick linear machine tools and linear servo drives with planar linear motors are always a unified mechatronic system.

Both the panels of magnets and the blocks of EM coils of Sodick planar linear motors are rigidly mounted to the massive structures of the machines, which completely eliminates any deformation of the parts of the linear motors and machine tools.

Sodick Machine Tool Servo Drives

Flat Linear Motors

Ideal structural rigidity

Sodick AQ327L inside design

Just try bending a cast-iron frame or column!
Or a massive table!

Sodick Linear EM Core-Coil+NdFeB Magnets

The gap between magnets and coils
is always
constant – 0.4 mm.

Massive cast iron structures to which the EM coils are mounted ensure perfect heat dissipation. Even if the coil heats up at a very high load, the heat instantly taken in and absorbed by the massive cast-iron structures.

What are linear motors in EDM for?

dead zone ball-screw vs linear
Sodick linear servo drives with flat linear motors are free from backlashes and dead zones

As a result, the gap is continuously kept in a state maximum of the ideal and at each moment constantly changing sparking discharges are maintained at the ideal energy state. This is what ensures a sharp increase in both the productivity and the quality of EDMing.

The tool in EDM process is electric spark. Or controlled spark discharges of various intensity and other parameters. Spark discharges are generated in the inter-electrode gap or the gap between a workpiece and an electrode. Characteristics of spark discharges to a very large extent depend on the size of the spark (inter-electrode) gap. The optimal gap means optimal processing conditions and, therefore, maximum productivity and machining quality. If the gap is larger or smaller than necessary, productivity and quality are lost. Ideally, at each moment of the working servo feed, the gap should be equal to the command value (specified by the CNC).

Conventional ball-screw drives, due to large losses in the mechanisms for converting rotational motion into linear motion and inertia (backlashes, dead zones) provide feed to command points only with a wide approximation invariably missing the ideal command point. As a result a ball-screw EDM only a small part of the time works for with the optimal spark gaps and, accordingly, in optimal energy modes (maximum productivity modes).


In linear motors, there is no conversion of rotational into linear motion, no ball screws, no gear or belt reducers. The motor moves with the moving part. The dead zone is almost negligible. Feed accuracy reaches microns and fractions of a micron with instantaneous corrections of electrode position when gap state changes.

Flat linear motors are what Electric Discharge Machines have been missing since their inception

Inert ballscrew drives cope with this task rather poorly. 
Flat linear servo drives keep the inter-electrode gap optimal by far more efficiently!

Sodick flat linear drives has come as a revolutionary game-changer in EDMing!