A reader of Control Engineering recently asked, “When I hear the sound of a ball screw that’s beginning to fail on a CNC milling center, I have to wonder: Isn’t there a better way to get that kind of linear movement? Are there other technologies?” We put that question to John Meyer at Siemens Motion Control Group, and he suggests linear motor technology.

        Stator and rotor of a linear motor is simil

        Linear motors have not been part of the progression of modern machine design that has seen quantum leaps in control technology, says Meyer. Rather, modern machines stillCONTROL ENGINEERING China版权所有, for the most part, use slide propulsion that was designed in your grandfather’s day. We have gone from tape-driven NC machines driven by dc servo motors and ball screws, to sophisticated CNC controls that can take a CAD file and produce a machine program at the touch of a button, right on the machine. To drive the slides on this modern machineCONTROL ENGINEERING China版权所有, we have progressed to ac servo motors driving ball screws. And maybe we also updated the slides from box way to truck and rail, but how are we driving these slides? Servo motors and ball screws.
        Linear motors enable maximum precision and dynamic performance in various motion control tasks. These include not only rapid traverse, but slow constant speed traverse of machine headswww.cechina.cn, spindle slides, tool management systems, part handling devices and more. There are considerable cost savings when various mechanical components are replaced by simple and efficient linear motors. These motors provide a total drive system, offering reliability, precision, high dynamic stabilitywww.cechina.cn, low maintenanceCONTROL ENGINEERING China版权所有, and improved production time.
        What is a linear motor?