Introduction: magnetic bearings in the application of high speed machine tool spindle - bearing knowledge

Magnetic bearings used in 100000 RPM speed can be obtained on the high-speed spindle, on the one hand, can improve the effect of surface processing, on the other hand it is greater than that of traditional bearing service life. Although the technology is still in the prototype testing phase, but a lot of advantages has been fully reflected. Its performance is not the effect of heat, no wear and tear, in the case of overload can be automatically shut down. The traditional bearing for the spindle radial or axial support, allows the relative movement between inner ring and outer ring. Inner ring and outer ring are connected by a ball or roller, support also in between the three. The oil film bearing no ball or roller, it USES pressure oil for lubrication or cooling. The above two kinds of bearing has several one hundred years of application history. Magnetic bearings for rotating parts support way is different from the above two products. Magnetic bearing is a kind of non-contact bearing, it through the electromagnetic force between the moving parts are suspended in the fixed part. Also means that there is no friction, no wear and tear, and higher stability, and can obtain higher speeds. Electromagnetic force is mainly related to the size of the current and gas gap, gap sensors to collect data, the size of control system based on the input signal to adjust output current. Magnetic bearings is mainly composed of three parts: bearing and sensor: provide support for the spindle bearing, sensor for gathering location signals. Control system: be responsible for providing power, and according to the feedback signal to calculate the correct corrective force, to drive the different direction of the controller. Software system: responsible for calculation and output feedback signal. Magnetic bearing is the main drawback is that: large, need power supply, as well as the complex structure and algorithm.