| 摘要 |
PROBLEM TO BE SOLVED: To provide a bearing structure of a wheel spindle for preventing loosening of a bearing-constituting inner race in high speed rotation of the spindle shaft.SOLUTION: In a stepped sleeve 11, an annular inner surface of the stepped sleeve 11 being an inner race fastening spacer of an inner race 7, is reduced at an angle of 0.01-0.02 toward a grinding wheel 2 from an end surface of the inner race 7, and an annular oil passage groove 11d is provided on the annular inner surface. A spindle shaft 1 installed in a central empty space of the stepped sleeve is also provided with oil passages 1a and 1b in the radial direction toward the oil passage groove 11d of the stepped sleeve 11 from a position of the rotation axis O. A fitting surface of the spindle shaft 1 and a ball bearing 9 is filled with pressure oil supplied to the oil passage 1b and the oil passage groove 11d, and high speed rotation of the spindle shaft 1 is enabled, and also pulling-out work of the spindle shaft 1 and the inner race 7 from the inside of a cylindrical housing 4 is facilitated. |
