Ceramic ball bearings

Using the high sensitivity of piezoelectric crystal sensors, signal transformation calculation by the principle of discrete Fourier, figure 5, figure 6 is the use of PDB measured type A motorized spindle vibration spectrum. By figure 5 shows, motorized spindle front vibration acceleration volatile, resulting in a decline in the precision reducing, stiffness of the motorized spindle. The figure 6 shows, equipped with motorized spindle end of ceramic ball bearing vibration acceleration change is very small, dynamic precision of the spindle running high. Compared to two types of motorized spindle shows that using ceramic ball bearings and can effectively reduce the vibration of electric spindle, progress of the motorized spindle running accuracy and stiffness.Ceramic ball bearings

Trials found that equipped with ceramic SKF Bearings two types of motorized spindle, the rotational speed is low, there is a beginning (low speed) operation of poor stiffness and low accuracy of topic.
Analysis of thought, is mainly composed of bearing clearance effect of prestressing force and work change. Low speed, the pre-tightening force, bearing clearance is small, high rigidity, high speed, high-speed operation produce larger load, bearing internal overlay, both the actual bearing high speed is far more than the early pre-tightening pretightening force. Lead to high bearing temperature rise, low service life, easy to appear early sintering damage. To extend bearing life, the early stages of the ceramic ball bearing pre-tightening force is smaller. But early pre-tightening force is too small, the spindle starts, ceramic ball bearing clearance is big, big deformation, poor stiffness during operation. The motorized spindle vibration increase, seriously affect the machining precision of motorized spindle. The solution is to research and development bearing preloaded force can transform organizations. There are two main measures: (1) the implementation of fixed position pre-tightening force transformation: (2) takes the running accuracy, low speed, the implementation of preloaded fixed position, high speed, the pre-tightening force can transform organizations.Ceramic ball bearings
The above theoretical and experimental analysis shows that:

In the same condition, the ceramic ball bearing than steel bearing is more suitable for high speed running condition. Ceramic ball bearing was applied to the design, manufacture of high-speed spindle unit, can effectively improve the limit of the spindle rotation speed, reduce the vibration of the high-speed spindle, spindle running accuracy and stiffness.

Application of ceramic ball bearings and can prolong the service life of motorized spindle, simplify the lubrication system of form a complete set with them. But to solve under the condition of low speed, poor ceramic ball bearing stiffness and low accuracy of topic.Ceramic ball bearings