| 摘要 |
PROBLEM TO BE SOLVED: To provide a pumping seal capable of reducing both of an axial dimension of a pumping groove row and an axial dimension of a lower capillary tube seal portion.SOLUTION: In a bearing device having a static shaft 22A, an upper annular portion 23A, a lower annular portion 24A, and a sleeve 311A, an outer peripheral face of the upper annular portion includes: a cylindrical face 71A; and an inclined face 72A positioned above the cylindrical face. An axial length of the cylindrical face is shorter than an axial length of the inclined face of the upper annular portion. A pumping groove row 831A is formed on an upper face of the sleeve or a lower face of the upper annular portion, and an axial dimension of the pumping groove raw can be reduced. An upper interface 401A of a lubrication oil is positioned on an upper capillary tube seal portion 4A, and a lower interface 402A of the lubrication oil is positioned on a lower capillary tube seal portion 42A. As an opening angle of the upper capillary tube seal is larger than an opening of the lower capillary tube seal portion, a volume of the lubrication oil held on the upper capillary tube seal portion is reduced, an axial dimension of the lower capillary tube seal portion can be reduced, and an axial dimension of the beating device can be reduced. |
