Patent ID: 7523556
Filing Date: 2009-04-28
Classification: A44C,Y10T

Abstract:
1. A ring expansion device for expanding the circumference of a ring shank, the ring expansion device comprising an expansion unit that is attachable to an inner surface of the ring shank outside the ring shank the expansion unit comprising: a first, hollow tubing section, an expansion pin or shaft having a first end portion mounted in the first tubing section, and a second, hollow tubing section slidably supporting an opposite, second end portion of the expansion pin or shaft; the second end portion of the expansion pin or shaft within the second tubing section comprising a single domed end, the single domed end being opposite the first end of the expansion pin or shaft, the domed end being engageable with a receiving hole in the second tubing section; wherein the expansion unit is portable and movable from one existing ring shank to another.