Centering device and system for driving ring

摘要

A centering device includes a pivoting part configured to pivot around a first axis that extends along an axial direction of a hole formed in the pivoting part; a roller attached to a first end of the pivoting part and configured to rotate; a rod attached to a second end of the pivoting part and configured to move along a second axis; a spring mechanism enclosing a part of the rod and configured to apply a biasing force to the pivoting part; and a rod housing configured to receive an end of the rod and to allow the rod to freely move through the rod housing.