System and method for electropolising devices
A system and method is described for electropolishing tubular metallic prostheses. In one aspect, the system provides a continuously changing set of points of contact between anode and prosthesis. In another aspect, the cathode is given a conical shape to correct for current concentrations that would otherwise exist and unevenly affect the amount of electropolishing over the length of the prosthesis.
1. A system for electropolishing a tubular metal prosthesis positioned in an electrolyte bath, the system comprising:
a first and a second cylinder positioned parallel to each other and spaced apart sufficiently to support the prosthesis when the prosthesis extends parallel to the first and second cylinders;
a wire element configured to extend through the tubular prosthesis and to bias towards the two cylinders, whereby the wire element is capable of contacting an inner wall of the tubular prosthesis to urge the prosthesis into contact with the first and second cylinders;
wherein, frictional engagement between the cylinders and the prosthesis causes the prosthesis and the cylinders to rotate in unison if any one of the prosthesis and cylinders rotates, whereby, when the prosthesis rotates, the wire element remains in biased contact with the inner wall through a continuously changing set of points of contact;
wherein the wire element is capable of conducting a charge and passing the charge into the prosthesis through the continuously changing set of points of contact; and
a motor configured to rotate a first magnet located outside the electrolyte bath, and wherein the first cylinder includes a second magnetic flywheel rotationally mounted on the first cylinder, whereby rotation of the first magnet outside the bath causes rotation of the second magnetic flywheel inside the bath, thereby causing the first cylinder to rotate.
2. The system of claim 1 , wherein the wire element is configured to rotate, and thereby, through frictional engagement with the prosthesis, to cause the prosthesis to rotate.