Patent ID: 8647170

Claim:
An at least three-point, fixed-spindle floating-platen abrading machine alignment apparatus comprising: a) at least three rotary workpiece spindles having rotatable flat-surfaced spindle-tops, each of the spindle-tops having a respective spindle-top axis of rotation at the center of a respective rotatable flat-surfaced spindle-top for each respective rotary workpiece spindles; b) each of the at least three workpiece spindle-tops having a respective axis of rotation perpendicular to the respective spindle-tops' flat surface; c) an abrading machine base having a horizontal, nominally-flat top surface and a spindle-circle where the spindle-circle is coincident with the machine base nominally-flat top surface; d) a workpiece spindle alignment spindle having a flat-surfaced rotary spindle-top, the workpiece spindle alignment spindle-top having an axis of rotation at the center of the workpiece spindle alignment spindle-top; e) a distance measurement arm device mounted on or attached to the workpiece spindle alignment spindle-top; f) at least one distance measurement sensor attached to the distance measurement arm device; g) wherein the at least one distance measurement sensors is attached at respective positions on the distance measurement arm to provide distance measurements to be made from the respective at least one distance measurement sensors to selected target points on the respective surfaces of the at least three workpiece spindle's rotary spindle-tops or to selected target points on the machine base top surface; and h) the workpiece spindle alignment spindle is configured to allow the at least one distance measurement sensors measurement distances from the respective at least one distance sensors to respective selected target points on the respective surfaces of the at least three workpiece spindle's rotary spindle-tops used to co-planar align the flat surfaces of the at least three workpiece spindle's rotary spindle-tops.