Self-pressurizing gas supported surface-roughness bearing

Apparatus for rotating a load having a longitudinal axis extending through a center of gravity, comprising:

• a. a bearing assembly coupled to rotate the load about the longitudinal axis and including
• i. a cylindrical bearing sleeve centrally aligned with the longitudinal axis and having a cylindrical surface including a first bearing surface including a random surface texture with a first R.sub.a roughness profile;
• ii. a cylindrical bearing shaft positioned coaxially within the bearing sleeve and having a cylindrical outer surface with a second bearing surface including a random surface texture with a second R.sub.a roughness profile, wherein the sum of the first and second R.sub.a roughness profiles falls within the range of from about 18 to about 60 and wherein the bearing sleeve and bearing shaft are aligned along the longitudinal axis such that the first and second bearing surfaces overlap;
• b. drive means for establishing a relative rotational velocity between the bearing sleeve and the bearing shaft where the relative rotational velocity generates a bearing stiffness force and causes the overlapping bearing surfaces of the sleeve and shaft to lift off and break contact;
• and
• c. the bearing sleeve and shaft having a geometry dimensional to maintain a predetermined mean spacing between the first bearing surface of the sleeve and the overlapping second bearing surface of the shaft of from a minimum of about seventy-five micro inches to a maximum mean spacing where the first and second bearing surfaces fail to lift off and break contact.

A self-pressurizing gas supported bearing comprising:

• a. a first bearing element having a longitudinal axis and a curved inner bearing surface with a random surface texture having a first R.sub.a roughness profile;
• b. a second bearing element positioned coaxially within the first bearing element and having a curved outer bearing surface with a random surface texture having a second R.sub.a roughness profile, wherein the sum of the first and second R.sub.a roughness profiles falls within the range of from about eighteen to about sixty and wherein the first and second bearing elements are aligned along the longitudinal axis such that the inner and outer bearing surfaces overlap;
• c. drive means for establishing a relative rotational velocity between the inner and outer bearing surfaces where the relative rotational velocity generates a bearing stiffness force and causes the overlapping bearing surfaces to lift off and break contact;
• and
• d. the inner and outer bearing surfaces having a geometry dimensioned to maintain a predetermined mean spacing between the overlapping surfaces of the first and second bearing elements of from a minimum mean spacing of about seventy-five microinches to a maximum mean spacing where the inner and outer bearing surfaces fail to lift off and break contact.