Patent ID: 7887032

Claim:
A self-centering control rod apparatus for maintaining a control rod in an equilibrium position when no external operating forces are applied, the apparatus comprising: a first and second support bracket, each with a collinear opening; a bushing supported by the first and second support bracket openings such that the bushing passes through both support bracket openings and linearly translates relative to the support brackets, the bushing comprising: an axial centrally located opening through which the control rod linearly translates relative to the bushing; and a first and second spring preload device, each preload device positively retained by the bushing, wherein the first spring preload device is located on one end of the bushing outside of the space between the brackets while the second spring preload device is located near the center of the bushing in the space between the brackets; a first spring attached to the control rod by an attaching means on the end outside of the first bracket, wherein the spring end opposite the attaching means abuts the first spring preload device, and wherein the spring is partially compressed between the attaching means and the first spring preload device; a second spring, wherein one end of the second spring abuts the first bracket on the inside of the first bracket and the other end of the second spring abuts the second preload device, and wherein the second spring is partially compressed between the first bracket and the second spring preload device; and a travel stop device retained by the control rod such that the travel stop device maintains contact with the bushing, at the bushing end opposite that of the first spring preload device and outside the first support bracket, when no external operator forces are applied.