Hydrodynamic bearing for machine tool spindle - utilises oil pressure to reduce spindle deflection and damp vibration

摘要

The spindle of a machine tool is supported by roller bearings. The combined effect of the overhung weight of the chuck and the force exerted by the cutting tool causes the spindle to deflect and vibrate. To counteract this deflection, a hydrodynamic bearing (7) is installed midway between the roller bearings. Oil is supplied and a hydrodynamic pressure is created by the rotation of the spindle. As the spindle deflects the bearing, clearance is reduced on the side opposite to the load. This reduced clearance generates a higher dynamic pressure which reduces the deflection and also damps out any vibration.