Patent attributes
Embodiments of a high-speed rotatable workpiece abrasive polishing head are disclosed that allow flat surfaced hard material workpieces or sapphire or semiconductor wafers to be polished at high abrading speeds that can use water-mist cooled quick-change fixed abrasive island-type discs. Workpieces can be quickly attached with vacuum to a rotatable workpiece plate having a curved (e.g., spherical) bearing with an offset spherical center of rotation located at the workpiece abraded surface. Abrading contact there prevents lateral abrading friction forces from tilting workpieces and causing non-flat workpiece surfaces. The workpiece carrier plate can be rotationally driven by a floating drive shaft having a spherical spline head that contacts the workpiece carrier plate at a position close to the workpiece abraded surface to avoid tilting of the workpiece due to the shaft-applied workpiece rotation forces. The workpiece head can allow the workpieces to either float in contact with the abrasive or be held in rigid contact with the abrasive.
