| 摘要 |
PROBLEM TO BE SOLVED: To improve the sealing action of a grinding spindle bearing and to improve the service life by comprising an annular gap for accommodating the reserve of the fluid paste medium. SOLUTION: A lower spindle bearing 28 downwardly directed in the axial direction is supported by an end wall 33 radially retracted inwardly on the midst of a bearing flange 32. An axial upward end wall 33 supports a seal ring 34 formed as a radial waveform seal ring from its back surface. A same type second seal ring 36 is arranged to the seal ring at a specified interval in the axial direction. An annular chamber between the seal rings 34, 36 is filled with the fluid paste medium. The medium is useful as a dust barrier, and couples and holds the dust moving toward the lower bearing 28 along the grinding spindle 26. The end surfaces differently shaped like a mirror image, of the seal rings 34, 36 are opposite to one another. |
