1. Field of the Invention
The present invention relates to precision journal bearings for high speed precision drive shafts. More particularly the present invention relates to high speed, internally lubricated, hydrodynamic journal or spindle bearings finding particular but not necessarily exclusive utility for magnetic media drive mechanisms.
2. Description of the Prior Art
Bearings of the character embodying the present invention are disclosed in U.S. Pat. No. 4,795,275, issued Jan. 3, 1989, to F. Titcomb and J. Cordova, for "Hydrodynamic Bearing." Such bearings are also disclosed in U.S. Pat. No. 4,596,474, issued Jun. 24, 1986, to F. Van Roemburg; U.S. Pat. No. 4,726,693, issued Feb. 23, 1988, to J. Anderson and R. Sleger; U.S. Pat. No. 5,067,528, issued Nov. 26, 1991, to F. Titcomb and J. Cordova; and U.S. Pat. No. 5,112,142, issued May 12, 1992, to F. Titcomb and J. Cordova. Such hydrodynamic bearings include a bearing sleeve with an internal journal bushing press fitted therein and in which is journaled a precision shaft, with provision between the shaft and bushing for incorporating lubricants. Thrust bearings are mounted on the shaft on opposite sides of the bushing. Flats are conventionally machined on the exterior surface of the bushing before press or shrink fit assembly into the sleeve to provide axially extending pressure equalizing lubricant passages in the bearing, with ports or passages through the bushing for conducting lubricant to the shaft journaled in the bushing and to the thrust bearings.