BALL BEARING FOR SPINDLE PIVOT SECTION OF MACHINE TOOL, AND SPINDLE PIVOT DEVICE OF MACHINE TOOL, USING THE SAME

摘要

A ball bearing for spindle turning device for use in the spindle turning device of a machine tool, and a spindle turning device for a machine tool using the same, which is compatible with machine tools whose recent trend is for more composite configurations while maintaining and achieving higher accuracy (higher rotational accuracy), greater stiffness and reductions in torque and heat generation is to be provided. In a ball bearing for spindle turning device for use in the spindle turning device of a machine tool, the sectional size ratio (B/H) between the axially cut sectional width B and the radially cut sectional height H is set to be (B/H) < 0.63 where it is a single row ball bearing or the sectional size ratio (B2/H2) between the axially cut sectional width B2 and the radially cut sectional height H2 (B2/H2) < 1.2 where it is a double row ball bearing.