ROTARY HOLDER FOR CYLINDRICAL WORK

PURPOSE:To simply hold so as to be rotatable, while making a centering process, a cylindrical work having a circular opening in the center of an end disk thereof without any blemish on the cylindrical surface. CONSTITUTION:A freely expandable linkage 14 is inserted into a circular opening (a2) in the center of end disk (a1) of a cylindrical work (a). The linkage, when pulling back, engages with the inner surface of the disk to press the work on the tapered portion 9b of a centering cone 9, allowing the work to be centered. Furthermore, the end disk (a1) is pushed to force the cone 9 to retreat to press the outer surface of the end disk perpendicularly to the axis of a rotatable shaft 8 to perform measurement or correction of runout, with the work being held and rotated between the end disk and the linkage. This does not clamp any outer surface, allowing no blemish.