Abstract: A system and method are described for ballizing and measuring a workpiece bore hole. In one embodiment, a ballizing unit having a distal end removably coupled to a ballizing member moves the ballizing member from a first position within the bore hole to a second position. A metrology unit having a distal end removably coupled to the ballizing member moves the ballizing member from the second position back to the first position. A sensor detects a force exerted on the ballizing member by the workpiece at a third position, which is located between the first and second positions.

Abstract: A fluid dynamic bearing capsule assembly having integral lubricating fluid recirculation paths for insertion into a disc drive hub for a data storage device that eliminates the need for machining recirculation paths directly into the hub.

Abstract: A system and method are described for ballizing and measuring a workpiece bore hole. In one embodiment, a ballizing unit having a distal end removably coupled to a ballizing member moves the ballizing member from a first position within the bore hole to a second position. A metrology unit having a distal end removably coupled to the ballizing member moves the ballizing member from the second position back to the first position. A sensor detects a force exerted on the ballizing member by the workpiece at a third position, which is located between the first and second positions.

Abstract: An improved hydrodynamic bearing design and method for fabricating a hydrodynamic bearing is disclosed, which incorporates a filling groove so that oil or other lubricating fluid can be efficiently inserted into the bearing gap without risking the loss of fluid during operation; the method provides for fabricating the hydrodynamic bearing and its oil filling groove so that the efficiency of the manufacturing process is not compromised. The same grooving tool which forms the hydrodynamic bearing is scraped across an abutment on the sleeve which supports the counterplate to form a shallow filling groove under the counterplate.

Abstract: A gap setting apparatus incorporates an air gage to measure the pressure drop (and indirectly the flow rate) of air through a gap of a hydrodynamic bearing, while facing sections of the bearing are moved closer together. The measured pressure drop can be correlated to the actual bearing gap and monitored to determine when the proper gap has been achieved. More particularly, the inner and outer elements of the bearing are clamped in separate carriers and are held in place. The carriers are then moved toward one another so that the inner or shaft portion of the bearing slides into the outer or sleeve portion of the bearing. To accurately set the gap between the two, an air hose with an air gage attached to it is attached to one end of the bearing gap; air is pumped through the bearing gap, exiting through the opposite end of the gap, By testing a set of reference motor parts, a high end and a low end of an acceptable bearing gap range can be established, and the corresponding air gage readings obtained.

Abstract: An improved hydrodynamic bearing design and method for fabricating a hydrodynamic bearing is disclosed, which incorporates a filling groove so that oil or other lubricating fluid can be efficiently inserted into the bearing gap without risking the loss of fluid during operation; the method provides for fabricating the hydrodynamic bearing and its oil filling groove so that the efficiency of the manufacturing process is not compromised. The same grooving tool which forms the hydrodynamic bearing is scraped across an abutment on the sleeve which supports the counterplate to form a shallow filling groove under the counterplate.

Abstract: A method of fabricating a spindle hub assembly (90) including precision machining critical surfaces of the hub components (60, 33) that mount onto a spindle shaft (30) and accurately locate the critical surfaces for positioning of bearing cones (35, 36) on the shaft in spaced relationship of bearing seats (34) on the hub (60, 33) to ensure stable rotation of the hub on the shaft.

Abstract: A hydrodynamic bearing useful as a bearing cartridge or as the cartridge may be incorporated into a spindle motor or the like, where the bearing includes a stationary shaft and two independent bearings, comprising a top cone and a bottom cone separated by a segment of the shaft. The bearing includes a sleeve rotating around and surrounding the shaft, and the top cone and bottom cone and defining a narrow gap between the sleeve and the shaft and cones. Sealing plates are supported on the sleeve to seal off the ends of the bearing and are located along the shaft beyond the cones. A gap also exists between an interior surface portion of each cone and the shaft. Thus, separate flow paths are established, one around the top cone and one around the bottom cone. By providing two independent paths, the flow rates do not have to be the same in each conical flow path for the bearing seals to function properly.

Abstract: A method for setting a gap at or near an optimum width in a hydrodynamic bearing defined between a shaft having end pieces, the end pieces having axially opposing exterior sides which are not parallel, the end pieces being adjustable axially, and a surrounding sleeve comprising independently supporting the shaft and the sleeve to be capable of finely positioned relative motion, in which adjustment is accomplished by moving the shaft and the sleeve together to form the gap with respect to the end pieces and the sleeve and supplying pressurized air to an opening to the gap to cause air to flow through the gap, while monitoring an air pressure drop due to the air flow through the gap while the end pieces are adjusted.

Abstract: An apparatus for forming grooves in the surface of an article is disclosed. The apparatus includes a cage which has a circular cage wall with an annular pattern of holes in the wall. The apparatus also includes a plurality of spherical balls, each rotatably disposed in a respective hole of the cage wall and has a diameter greater than the wall thickness. The apparatus further includes a pin located within the cage, the pin has a circumferential groove in a plane coincident with the plurality of spherical balls and holes in the cage wall so that the pin holds the balls in the groove, the balls protruding through the cage wall and engaging the surface of a workpiece to be grooved so that the balls roll in the groove in the pin and, with movement of the workpiece and the apparatus, cause grooves to be formed in the interior surface of the workpiece.