| 摘要 |
In a dynamic pressure bearing having a sleeve and a shaft fitted in the sleeve, dynamic pressure generating grooves are formed on an outer cylindrical surface of the shaft. The dynamic pressure generating grooves consist of first oblique grooves disposed in a first cylindrical zone of the outer cylindrical surface, second oblique grooves disposed in a second cylindrical zone spaced from the first cylindrical zone in an axial direction, and cross grooves (or generally X-shaped grooves) disposed in an intermediate cylindrical zone between the first and second cylindrical zones. The first oblique grooves are oblique in a direction with respect to a generating line of the cylindrical surface and the second oblique grooves are oblique in a direction opposite to the direction in which the first oblique grooves are oblique. The cross grooves consist of third oblique grooves which are oblique in a direction with respect to the generating line of the cylindrical surface and fourth oblique grooves which are oblique so as to intersect the third oblique grooves. A clearance between the shaft and the sleeve is filled with a lubricant.
|
